Just adding more to your point, this has been said at the beginning of both Stormblood and Shadowbringers. Then people at the media tour are like "Yeah, guys. It seems that there's more damage going out." but it never really ends up being that way in the end. since during the media tour no one knows the dungeon yet and thus takes more damage than usual. That's about the only time healing while leveling the MSQ is fun. Could this change with the stat squish and perhaps less overall increases between ilvls? Sure... it could... but SE is also scaling mob damage and health, too, so it's far more likely to end up the exact same.
I'm kind of agonizing over what to do come Endwalker. On one hand, I want to get through the story first and I have done so on WHM since 2.0.... but the solo instances and leveling experience on healers is... awful. I've never been a huge fan of scholar, but since SMN piggy backs on it, it has been a tempting alternative... I suppose PLD or DNC are my other options. I'm interested in SGE... but I don't really want to level it from 70-80 before doing the MSQ for Endwalker. ><