Not at all. There are several things SE can do, and many of them would be simple.
The easiest would be to impose gates on all existing dungeons so that pull size wasn't a decision-making process. They could remove the gates for non-DF parties so as to soothe people who run in preformed groups. That would immediately relieve a lot of the healer / tank stress, because nobody would be whining about speed-pulls if the dungeon mechanics removed any possibility of it. Less uncertainty, less room for DPS-role players to pressure the tanks - better experience.
There are also other options. Making Enmity maintenance more interesting would help; tanks shouldn't be forced into "tanking mode" or "damage-dealing mode"; they should have multiple options within the tanking role. Perhaps a Regen-like effect for Enmity? Who knows; that's up to SE to sort out. Either way, giving tanks different ways of fulfilling their role can only help matters. The most difficult (but likely most effective) solution would be to re-balance dungeons around a 5- or 6-person party setup, with the additional slots going to DPS-role players. Unfortunately, the only convenient window of opportunity for a change like that is the launch of a new expansion, which would naturally allow for a "all dungeons above level X" setting, so that SE doesn't need to re-balance older dungeons to meaningfully impact queue times.
Hell, even offering a simple apology to people for so badly miscalculating with the RDM / SAM decision would go a long way. It wouldn't fix the problem, but at least players wouldn't feel quite so insulted. SE got up on their high horse for months leading up to the release of Stormblood, all to justify the release of two DPS-role jobs without any healer or tank options. It backfired, badly. They should suck it up, apologize, and pledge to learn from it (as well as some of the more horrific 4.0 combat changes, which single-handedly destroyed SCH populations and weakened WAR / DRK / WHM numbers).
Or, y'know, we could follow your snarky suggestion.