I agree completely and I think that movepool power creep has been a huge factor in the modern games feeling easier.
...In FRLG Bulbasaur learns 35 power Vine Whip at level 10 and 55 power Razor Leaf at level 22, assuming it’s been evolved into Ivysaur.
A somewhat important wrinkle that impacted a lot of Pokemon / moves from generation 1 for a lot longer than would be expected or rational is the phantom carryover of assumed Gen 1 move learning without relevant mechanics. Between Trapping moves like Wrap and Fire Spin, certain bad stat boosting moves like Amnesia and Agility, and High Crit Rate moves like Slash, many of these moves took until Gens 7, 8, and even 9 to be placed in level up movepools somewhere fitting for their power level. Funny enough, Razor Leaf on the Bulbasaur was moved forward to Level 22 from Level 30 in RBY, making it an exception that proves the rule; despite it getting it at a very normal time, Chikorita getting it extremely early, and other later Pokemon getting it at super reasonable levels, the Bellsprout line still learns the move at an incredibly late level 44 in SV.
I say it regularly, but I genuinely do not think GF has any idea of what they want game balance to look like, casually or competitively. Movepools are an obvious example of that, there's plenty of reasonably similar mons where one gets a bunch of coverage and the other gets STAB+Body Slam, but it goes for everything. If you asked one of the designers "How many neutral attacks should it take to KO a gym leader's ace in the midgame?", they not only would not have an answer, I suspect they've never even considered the question. (...) These are not questions that need hard rules for the answers, but they are questions which designers should be thinking about.
When looking at other games, which will adjust recharges or resource costs by 1% sometimes, it really feels like Pokemon chooses things almost at random.
I actually think Pokemon games had a remarkably consistent and crafted ingame balance for the earlier generations. RBY, RSE, and BW1 stand out to me as games that feel carefully considered for average players. The big reason that Pokemon doesn't tend to ask these kinds of design questions with high precision is that the player possibility space in Pokemon is just way higher than in other RPGs due to the sheer quantity of potential party members, and it's not a coincidence that these specific games are the ones with the highest proportions of newly introduced Pokemon in their regional Pokedexes. When Pokemon are added into games, traits like their base stats, typing, evolution requirements, EXP group, and more are completely locked, and while movepools aren't completely locked there tends to be a soft limit on the flexibility they have in regards to overhauls. Working in existing designs is always possible in these games, but having fewer and fewer viable levers to tweak is always a relevant issue to ingame balance and consistently leads to legacy carryover being the direct cause for ingame imbalances. (Think BW2's potential for super early Lucario)
By SwSh, the designers pretty much gave up on giving Pokemon deliberately crafted ingame functions. A trend you'll see when looking at movepools that change from USUM to SwSh is that moves became directly sorted in order by Base Power rather than being learned in a specifically chosen order, which in a few corner cases leads to confusing outcomes. Pokemon also forgo precisely designed progession in their level up movesets for moves learned every 5 levels, and with the move relearner being definitively changed from a resource dependent expert player gold mine to a quality of life feature that invalidates level up moves when used correctly it's hard to really care that much. With 400+ mon regional pokedexes becoming the norm, I can't help but resign myself to understanding this decision.
Finally, maybe the unpopular opinion embedded in all of this, but I think GF had a pretty strong grasp on creating new gameplay designs for Competitive by Gen 7 and the vast majority of Pokemon from that point have something pretty cool going on.