I think the ability Tinted Lens is a bit overrated. In theory, it sounds great: the ability to hit types that would usually take resisted damage instead takes regular damage is great, and it could allow mons to snowball the opposing mons. There have also been good Tinted Lens like Lokix, Yanmega, Venomoth, and even Butterfree in the Lower Tiers. But the reason Tinted Lens works with them is that they have the Bug Type, which has
7 resistances (Fire, Flying, Fairy, Steel, Poison, Fighting, Ghost) out of 18 types, the most of any type tied with Grass (Flying, Poison, Bug, Fire, Grass, Dragon, and Steel). When you remove these resistances, they would perform better as they would be able to hit harder, combined with U-turn (though not all bug mons get the move). However, most types only have 4-5 resistances, which wouldn’t really benefit them.
For example, Rock is seen as a mediocre type because of its poor defensive profile—5 weaknesses, only useful resistances are Fire and Flying —and its inaccurate physical moves, such as Rock Slide and Stone Edge. Offensively, however, they can be great, as it would be risky to switch in a Stone Edge that can crit or a Rock Slide that can flinch them, and the only Rock resistances are Fighting, Ground, and Steel. So it's really their lack of a defensive profile that’s holding them back, which is why Tinted Lens wouldn’t help them as much.
Tinted Lens also wouldn’t really help Psychic because the only types that resist Psychic are Psychic itself and Steel. The ability wouldn’t help them work against Dark types, as they are immune to it. But the reason why Psychic has fallen is not necessarily because of its offensive prowess (as having few resistances to Psychic and hitting for neutral is impressive), but because of its lack of defensive prowess against the rise of great Ghost Types, Knock Off, Pursuit (before Gen 8), and U-turn used by bug and non-bug mons. There are Sigilyph and Braviary-Hisui as Tinted Lens Psychic mons, but they don’t always use Tinted Lens; they sometimes run Magic Guard and Sheer Force, respectively.
There’s also the fact that most types would usually have coverage to take on their resists:
- Rock Types resisted by Steel? They usually run a ground move, like Earthquake, to strike back, and sometimes a fighting move, like Body Press.
- Fighting Types resisted like Flying, Bug, Ghost, Psychic, and Fairy? The former two can be handled by Rock moves, and fighting types usually have Knock Off to deal super effective damage against Ghost and Dark, whilst also acting as an item removal.
- Psychic walled by Steel, Dark, and opposing Psychic Types? The former two can be handled by Focus Blast, and the latter by Shadow Ball.
- Water Types usually have Ice moves to deal with Grass and Dragons, and Dragons usually have Flamethrower or Fire Blast to deal with Steel Types.
Unfortunately, since Bug attacks have many resistances and Bugs themselves have poor coverage against them, they usually struggle compared to others. That’s why most Mons with Tinted Lens happen to bug types; it’s needed to compensate for their lack of offensive prowess.
There are exceptions, like Heracross and Pinsir learning Rock and Fighting moves, Scizor having Close Combat to deal with other Steels, Masquerain having Water moves to deal with Rocks, and Venomoth having Energy Ball to deal with Rock and Ground Types.
But when you have to deal with many resistances, it would be hard to answer most of them without removing some or all of them.