While I agree in a vacuum, and I don't have a problem with Close Combat being a TM on paper, I have always kind of disliked the decision to let almost every Fighting-type have access to Close Combat after it became a TM.
And I'm not saying this because I think Close Combat is too good of a move per se, but rather from a flavor standpoint Close Combat becoming a more homogenous STAB for all Fighting-types really takes away from the variety and flavor that has always made Fighting-type Pokemon so interesting to me. What makes Fighting-type so interesting from a flavor standpoint is that there are so many powerful moves: Close Combat, Superpower, Hammer Arm, High Jump Kick/Jump Kick, and some weaker but more utilitarian moves like Brick Break, Drain Punch, and Power-Up Punch and whatnot, and there's a lot of interesting variety in Fighting-type attacks that are spread differently across different Pokemon. Because Fighting is an incredibly flexible type as to what kinds of designs it can invite into its roster, because there are so many different flavors and styles of Fighting-types, and back then not everything got Close Combat, but likely got another powerful Fighting STAB as an alternative, and this made things interesting from a gameplay standpoint as well as a flavor standpoint. You have agile fighters, Pokemon that focus on sheer physical strength and muscle power, some that specialize in some form of martial arts, and so on and so forth, and that's what has made Fighting such a fun and colorful type to me from a standpoint.
Like for instance, we have three Fire/Fighting starters: Blaziken, Infernape, and Emboar. Before Gen 8/9, they all had different Fighting-type techniques they could learn naturally. Infernape was the only one of the three who learned Close Combat, and this fits because Infernape is a slim, agile monkey and Close Combat flavor wise is the user getting in close and firing a relentless flurry of attacks at a rapid pace. When you look at Infernape, it is very believable for Infernape to pull off Close Combat from a flavor standpoint. Like the other move it learns naturally is Mach Punch, which is firing a punch at a mach speed. This gives Infernape a distinct flavor overall, not just from the other two Fire/Fighting starters but as a whole. Meanwhile Emboar is more of a slow, heavyweight fighter with a large build, and the strongest Fighting moves it learned are Hammer Arm and Superpower. Superpower is as strong as Close Combat but instead lowers Attack and Defense instead of both defenses, giving it a bit of a downside there, but flavor wise it fits Emboar well distinctly because a heavyweight like Emboar is the kind that would concentrate a lot of physical power and then deliver a single, powerful blow to the opponent. Blaziken learns kicking moves like High Jump Kick, and naturally it learns Double Kick and Blaze Kick, because it's a fighter that specializes in kicking. This allows the three of them to feel distinct from one another flavor wise.
I used those three as the prime examples but among the entire roster of Fighting-types the variety in flavor has always been interesting to me and Fighting-type's wide set of moves, each with rather limited distribution among Fighting-types, helped enforce that variety and flexibility. I don't mind other types being homogenous: elemental types like Fire, Water, Grass, Electric, and Ice are predicated on their element and don't invite too much variety in moves to begin with, Ground is a case where most attacks are iterations of "stomp the ground and cause a tremor", like Bulldoze, Magnitude, and naturally Earthquake, and so on and so forth. But I feel Fighting is one of those cases where at least before Gen 8, the variety in its flavor in both moves and Pokemon was/is a big part of its identity.
And I'm not saying this because I think Close Combat is too good of a move per se, but rather from a flavor standpoint Close Combat becoming a more homogenous STAB for all Fighting-types really takes away from the variety and flavor that has always made Fighting-type Pokemon so interesting to me. What makes Fighting-type so interesting from a flavor standpoint is that there are so many powerful moves: Close Combat, Superpower, Hammer Arm, High Jump Kick/Jump Kick, and some weaker but more utilitarian moves like Brick Break, Drain Punch, and Power-Up Punch and whatnot, and there's a lot of interesting variety in Fighting-type attacks that are spread differently across different Pokemon. Because Fighting is an incredibly flexible type as to what kinds of designs it can invite into its roster, because there are so many different flavors and styles of Fighting-types, and back then not everything got Close Combat, but likely got another powerful Fighting STAB as an alternative, and this made things interesting from a gameplay standpoint as well as a flavor standpoint. You have agile fighters, Pokemon that focus on sheer physical strength and muscle power, some that specialize in some form of martial arts, and so on and so forth, and that's what has made Fighting such a fun and colorful type to me from a standpoint.
Like for instance, we have three Fire/Fighting starters: Blaziken, Infernape, and Emboar. Before Gen 8/9, they all had different Fighting-type techniques they could learn naturally. Infernape was the only one of the three who learned Close Combat, and this fits because Infernape is a slim, agile monkey and Close Combat flavor wise is the user getting in close and firing a relentless flurry of attacks at a rapid pace. When you look at Infernape, it is very believable for Infernape to pull off Close Combat from a flavor standpoint. Like the other move it learns naturally is Mach Punch, which is firing a punch at a mach speed. This gives Infernape a distinct flavor overall, not just from the other two Fire/Fighting starters but as a whole. Meanwhile Emboar is more of a slow, heavyweight fighter with a large build, and the strongest Fighting moves it learned are Hammer Arm and Superpower. Superpower is as strong as Close Combat but instead lowers Attack and Defense instead of both defenses, giving it a bit of a downside there, but flavor wise it fits Emboar well distinctly because a heavyweight like Emboar is the kind that would concentrate a lot of physical power and then deliver a single, powerful blow to the opponent. Blaziken learns kicking moves like High Jump Kick, and naturally it learns Double Kick and Blaze Kick, because it's a fighter that specializes in kicking. This allows the three of them to feel distinct from one another flavor wise.
I used those three as the prime examples but among the entire roster of Fighting-types the variety in flavor has always been interesting to me and Fighting-type's wide set of moves, each with rather limited distribution among Fighting-types, helped enforce that variety and flexibility. I don't mind other types being homogenous: elemental types like Fire, Water, Grass, Electric, and Ice are predicated on their element and don't invite too much variety in moves to begin with, Ground is a case where most attacks are iterations of "stomp the ground and cause a tremor", like Bulldoze, Magnitude, and naturally Earthquake, and so on and so forth. But I feel Fighting is one of those cases where at least before Gen 8, the variety in its flavor in both moves and Pokemon was/is a big part of its identity.