I do not agree.
You can make rules that let no space for power gamer.
In fact 5ed is very good at that.
A Dm can shut down most pc optimization with a few changes to rules.
No SS and GWM. No MC for paladin. Eldritch blast multi beam based on warlock level.
In first edition optimization was not really possible.
No feat, no ASI, no sub classes choices.
Optimization and power gaming is derived from card game and war game, and pvp computer game.
It is not really at heart of DnD.
Other than 5e, the only edition I would play is AD&D 1st edition. I feel you. I do not like or play MMOs, but I think you might be overlooking the point due to your preferences (which I might actually share with you).
First, you say you can shut down optimization--by modifying the game! That sort of moves the goal posts. Making rules so the game is different does not discuss the game as is--RAW.
Second, the real thrust of my post is that pretending and playing a role is not the same thing as getting better at a role due to higher bonuses or interactions of bonuses. As a result, I think we need to think about preferences and how much is too much for our own individual taste--in lieu of turning our noses up (a priori) at people that try to be effective.
I do not know too many players (any!) that would simply ignore ASI or feats at appropriate levels in this edition.
I personally walk a line. My warlock for example has reasons to be obsessed with wizardry and death. He will take 1-2 levels of wizard. Abjurer is "better" but the character story says necromancer (should I take two levels).
I could just say in his story that these things are true and initially that is what I did. Then I started thinking it would be fun to be MORE EFFECTIVE in the role and story I created. I could have the same story without 1-2 levels in wizard and it would still be the story.
I know it is subtle navel gazing of a fan-boy...but that is the thrust of my argument.