Quoted By:
The problem with pokemon is how some mons directly outclass others, limiting all viability to an elite consisting of ~15-20 mons who can be considered "the best" in what they do.
For example, greninja is the very best sweeper in the metagame, able to destroy entire teams singlehandedly if they aren't prepared for it, of course, there are other great pokemon who can fill the same task as greninja, such as medicham and roserade, but the superiority of greninja doesn't leave any real reason to use any of these over it, neglecting greninja in favor of a lesser sweeper will only cripple your power and prevent you from getting as far as you would if you used one.
In case you wonder, no, I'm not here to bitch about how my "bro" gets shat on by a better pokemon, I'm just telling you this.
The existence of pokemon who are objectively superior to the rest severely reduces diversity in the metagame to the point where it gets radiculous, lando-t for example has 40% usage on smogon, while megamence or megacross are staple for all battlepot teams.
I'm not saying it is impossible to defeat these with lesser mons, but you don't have an actual reason to not use a pokemon that is higher up in the hierarchy, for example, infernape can be used to counter megacross, but greninja can do the very same thing while still being able to perform a plethora of other tasks.
No matter what "format" or "rules" you play by, the hierarchy will manifest in some way, block out lesser mons and make the metagame stale, repetitive and boring.
Now for the purpose of this thread, what could gamefreak do to force more diversity, not only in their own metagames, but in the franchise as a whole?