The idea of less survivable tanks with higher damage output had less to do with tank stance and more to do with gearing. If you chose to swap out your VIT accessories for STR or even STR pentamelds, you gained a much bigger boost to damage output. That's what let tanks be able to outperform physical ranged DPS at the time. Although an even better example of this was in early Stormblood, where they tried to remove STR from tank accessories such that your damage didn't scale up with gear upgrades, so everyone swapped off to the i270 relics from the Creator tier instead. You had to be a lot more active with your cooldowns, but in exchange you did significantly more damage.

I'm sure that tanks would be happy with that sort of design, especially if you put their damage back on par with physical ranged.