>>16800191It adds the mechanics without changing the base pokemon and is temporary.
Remember all the shit the gen 4 evos like Magmortar, Lickilicky, Probopass, and Rhyperior got? Hell Rhyperior still gets hate to this day.
Mega Evolutions allow the older mons to keep up with the power creep without divisive evos.
I personally dislike Mega Evolitons for the very reason of there probably not gonna be any more cross gen evos aside from more precious eeveelutions to bring in more girls and furfags.
Mons like Mawile, Manectric, Banette, Pinsir could have used the actual evos with some BST tweaking. A lot of other pokemon that got megas, like Scizor, Gengar, Gyarados, Blaziken, TTar, Garchomp, and Lucario don't need them.
Its an interesting concept, and I can understand it from a marketing perspective, but from a gameplay standpoint is execution could have been better.