Yes exactly.
I see this as a 'fundamental design problem'. Any solution that works would also require radically redesigning the game.
City of Heroes was one of the first MMOs to do scaling. It did it by scaling up. I could group with somebody and bring them up to my effective level but in so doing they only had their original abilities. The result was that nobody ever wanted to use it unless they were using it to speed level a friend. It was basically 'toxic' to group play.
FFXIV is kind of the next attempt at MMO scaling and did scaling down. This mostly works - but leaves the play a bit boring to higher level players.
ESO is the third attempt and it works, almost perfectly. BUT it only does this because your action bar is so small, you can fill it by a pretty early level - and the hundreds of abilities you can get after that are just 'better or different gameplay options'... but by the first dungeon even a 'noob' has something to bring and is fun to play...
- The ESO solution would NOT WORK HERE... That small action bar works because it's aim-based action combat, which has a lot of other issues (all of which would be hard to explain here as the engine is so radically different).
For what it tries to do, the FFXIV system more or less works. FFXIV is probably the "endgame" of the potential for tab-target MMOs... Action based MMOs are what we see in new games, and they're still in the early stages where none of them yet really have good combat systems for organized group play (BDO may have a great combat engine - but mostly because people use it to 1v1 PvP, not tank Coils or Castle Nathria or something. ESO combat engine probably works the best of the action-MMOs for group content, but that's 'best compared to other options in an action MMO' not best as in an actual great system... And this coming from a big fan of their system...).
So I think gaming is a bit at an impasse on this one.
If we gave low levels a few OGCDs though - we could at least make the scale down funner.