1) Auto attack crit rng on bosses was a horrible mechanic that had no place in the game. taking back to back crits putting a tank at 35% hp was something that healers could not account for with planning and in some cases basically lead to tanks dieng when they were mitigating properly to a tank buster + crit auto from full health.
2) When SE removed crit autos from the game they compensated by raising the average damage per auto from the bosses. E4S slaps tanks for 1/4 of their hp every auto attack at around 455 item level. TEA slaps both tanks for over 1/4 their hp every single auto on top of all the mechanics that are going on. many fights follow suit.
3) P2N is already a highlight that there is a ton of raidwide damage going our way, savage version is only going to be worse.
4) Every single fight in SHB had more tank busters than the first 3 minutes in godka besides E9S which was a joke of a fight once your team was on the same page. 2 part fights in general also have far more leeway with being difficult since there is a checkpoint to fall back to.
5) Shadowbringers as a whole had far more annoying mechanics for the PARTY than the entirety of Stormblood barring a few in O8S and O12S and even then average players had far more issues dealing with mechanics like conflag strike, light rampant, and lions in E6S, E8S and E12S respectively
Players as a whole have become relatively more competent and able minded to tackle harder mechanics, but this is still a team game in the end so fights should not be designed to be hell on just one job or another otherwise nobody in their right mind is going to want to play those jobs. lower player base participation = less content of that type.
also, clearing TEA I can tell you that having the tools the tanks had then was ABSOLUTELY something that was required on release. This is obviously ultimate content which is the highest of the high so my viewpoint there might be different to somebody that might only do extreme content.