>>35567194No, Megas were somewhat needed.
They did it wrong most of the time, but for some they were useful in terms of the meta.
Should things like Mewtwo, Gengar, Mawile, and Absol etc. have gotten one? No, obviously not. Powerhouses and things that were single stage and should have gotten a straight evolution shouldn't have gotten Megas.
For others like the Gen 1 starters which were nigh useless competitively? It absolutely was good for them since evolution chains are limited to 3 stages (and should be - it's one thing to have branching evolutions, but Charizard stage 48 being possible just invites even more power creep than we already have).
Bad follow through doesn't make the idea bad. Having a gun for defense or even just as a collection is a valid idea, for example, but if you keep 'em loaded, cocked, out in the open and have 12 kids running around to possibly find and play with it... Not so much.