This is a case where everyone is right. Yes, starting weak and becoming very powerful has been part of the D&D formula forever. But the HP bloat does nerf the wizard and the caster cleric.
Take the sleep spell for example. Sleep is a 5d8 spell. If joe goblin had 7 hp, three after poisoning the wine, then a sleep spell would take out 4-5 poisoned goblins or 3 full strength ones. Or many more on a lucky roll. But since goblins have 16 - 27 hp it is much less effective.
HP bloat / AC reduction has to change.