Exaggerated as in terms: Will every Pokemon without an evolution and low stats (which means is basically not doing too well in battle) now receive a Mega-Evolution instead of a possible normal evolution - like they did several times before (Murkrow for example)? It just feels wrong. Buffing weak Pokemon is fine but they shouldn't forget that there's still the default evolution from which many Pokemon would benefit even more.
It has been stated by people affiliated with Pokemon that there's a possiblity that all Pokemon will eventually get a Mega evolution. I, for one, detest the idea and hope it's an internet rumor, or something that they won't go through with. Would ruin the whole concept of Mega evolution, and the series itself.
Also I DO think certain Mega-Evolutions were unneccessary, making an already powerful Pokemon-Family slightly overpowered. I wish they'd just use the ME more "carefully" and not just throw them around like that.
That said, I still think Mega Evolution is great, I just think it's in danger of getting too much.
I fully agree with you. Mega Garchomp is one of the main ones I found unnecessary, but it being such a widely popular Pokemon, it made sense for Game Freak to grant it one in order to raise publicity and excitement for X and Y and the feature of Mega evolution. They have the ability to either bring life to underrated Pokemon, or abuse it and give Mega forms to too many Pokemon.