>>39763452Not entirely.
Megas, and Z moves had a critical flaw in that they took up an item slot, and megas, and z-moves could each only be used by one mon.
The really broken mega evolutions were only really because of their abilities. Ones like Mega Garchomp, and possibly mega Tyranitar are widely agreed to be worse than their originals.
Z-moves could be completely wasted by a well timed switch in. Rendering it doing half the damage, or doing absolutely no damage depending on the type of the z-move. This isn't even including the fact that a well timed protect could render the z-move ineffective, and waste it as well.
The key difference with Megas, and Z-moves with dynamax is that both of them had actual counter play with already available common tools. Dynamax forces you to also Dynamax since EVERY Dynamax attack carries a secondary effect alongside doing massive damage. WHILE items can be held.
Just imagine choice specs dynamax Hydreigon, and it's dynamax dragon, or dark type attacks. The problems really become clear with this particular gimmick unlike the past ones.