Basically. Unless you have numbers that literally change based on what you're doing (like, you have "trial potency" and "dungeon potency"), if you have one kit, then you need to pick what you balance around. And it would be absolutely retarded to balance around the experience of people who won't even perceive balance, and won't ever push close to the limit of their class.
As for the TOP no-healer clear being used to prove how bad healers are. Nah. It's just done to show it's possible. Ultimate challenge runs are to raiding what speedrunning is to playing a game, or clearing a Souls game without any armour. It's there to push the boundaries of what is possible within the game for no purpose other than "can it be done?". The guy with the pot on his head in Elden Ring wasn't soloing Melania with no armour to show how bad armour is.