The position locks and movement jank were not deliberately designed to allow for bullet hell level dodging. Let's not excuse lazy game design. It's not like FFXIV is the only game that makes you dodge AoEs. Most of the time, "north" is just whichever direction the boss is facing.

Positioning is not an all or nothing check designed specifically to cause wipes. It's how good tanks set up your team to do more damage. It's about optimization.

Your melee is on an add. They then rotate off onto the boss without losing a single GCD. Why? Because your tank placed them there. Your team has to move to a safe zone. Everyone gets there without losing a GCD on the boss. Why? Because the tank backstepped the boss in a timely fashion instead of booking it to safety. Your caster doesn't want to move for the next mechanic. They don't have to. Why? Because your tank repositioned the boss such that they are now in a safe zone. The ideal tank is the ultimate facilitator. You set up fights to allow your dps to do their job more effectively. You mitigate damage to ease the burden on your healers. You rescue/shield misplaced teammates from certain death. You push your dps to compensate for underperforming teammates. And sometimes, just sometimes, you solo the boss down the last few percent as the last player alive, with your entire team cheering you on. You are the carry. Anything less than this isn't real tanking.

If you want tanks, tanking needs to feel relevant again.