>>45750159>>45750171OK, let me take a stab at it
Adding Mega Forms allows for previously underpowered pokemon to get a temporary, 1 generation boost in power, which lets Gamefreak avoid having to add completely new permanent evolutions and lets them experiment with some out-of-the-box ideas.
Kangaskhan, for example, was absolute ass every generation after generation 1. Even in generation 1 it arguably sucked. But it was a very cool pokemon that I personally liked and always wanted to make work.
By giving Kangaskhan a mega-evolution, the meta is shaken up a bit, as Mega-Kangaskhan is a seriously strong pokemon. This makes players like me happy, it makes compfags happy, it lets kids experiment, and it doesn't mess up the game long-term because you can limit where you release mega-evolution stones. If they had just made mega-Kangskhan a new evolution, then any problems she would have (and eventually did) cause would the be permanent problems that require direct nerfs, an inelegant solution the devs prefer to avoid where possible.
Dynamaxing and Z-moves are bad imo because they don't actually increase diversity much. Since they affect all pokemon (with 3 exceptions), if you buff all pokemon equally, that just means you've powercrept the game up a bit. It's not like the PU-tier 'mons will now see more play, you've just upped the cap on possible strength.
By limiting Megas to certain specific 'mons, usually ones that either need some TLC and/or are fan-favorites, that actually increases the amount of viable stuff. If you give everyone everything, then the previously refined comps just get more refined.
