Power balance is not essential to the game. Every edition to date has had imbalances in power.
Some orders of magnitude greater than others.
And, 5e tries to evoke all of them, particularly the classic game, where, though balance was repeatedly called out as an objective, it was not much delivered.
We've been able to enjoy all of them.
The question is, though: enjoy in spite of imbalance, or because of it?
I think in the case of D&D, a lot of the fans who stuck with the game all through the TSR and 3.x/PF years found ways to leverage the game's unintentional imbalance, or intentional rewards for system mastery, and enjoy it /because of/ rather than in spite of them.
And, since that's most the game's history, right there, 5e really needs to continue supporting that sort of experience.
Even so, the OP's a fair theoretical discussion.