I 100% believe that a good reset every so often is in fact very, very good for the game. D&D would never have achieved the dominance it has with things like descending AC.
The problem is, there will never be a time at which the players can agree that such a thing is good or necessary. If the players do in general think such a thing is good and necessary, it's DEFINITELY been far too long. But they aren't wrong to want periods of stability and consistency either.
Being shackled to the design decisions of people from 20, 30 years before is, in a word, bad.