SE must be drunk.

[Kiteless]

The simple fact of the matter is that there's really not a whole lot that can be done to add further damage mitigation to tank stats without working to trivialize the role of healers (who already can end up getting quite a bit of time just to DPS themselves, depending on the fight). The only reason parry 'works' as a tank stat is that it's wholly insignificant in its function. At the end of the day, the base stat of vitality really ends up covering all the bases for pure tanking stats, and to add anything else with actually valuable impact would end up requiring a fundamental change in how the game's trinity functions. And you can't really nerf tank defenses to compensate, since in this situation, basic tank survivability is a required constant for the game to be playable. To this extent, the stat changes for tanks did very little to actually improve the state of the game, save for making bad DPS players feel better now that tank numbers don't beat theirs by quite as much.

Ultimately, there's really no way to do proper tanking secondary stats in this game. The best way to do it would be to just cut the stat entirely and accept that tanks are going to end up wanting to contribute DPS too.
If Square really wants to actually give tanks proper stats while not making DPS players jealous of their numbers, then they'd best focus on improving the functionality and utility of the DPS classes so that their unique abilities become more integral to the fight. On the other hand, that could also act to alienate players who do prefer to have their responsibility stay lax outside of enrage timers, which themselves are all pretty effortless now. So, as it stands, the problem with tanks doing respectable damage, if there even is one, really lies with how nonessential the DPS role has now become.