Yep. A huge number of AOEs and abilities are Physical damage even though they may look like fire/earth. A lot of the stuff in Titan is actually Physical too, only some of his abilities are earth damage. If you can parry it, it's physical.
This is why you don't understand the pointlessness of Parry. Just because you disagree with the logic doesnt make it false. Tank DPS is important in almost every raid encounter.
Tanks contribute less DPS than other DPSers but not by much. A tank who minmaxes their DPS will still be contributing a large amount of DPS to a party. Even if they put out 50% of the damage of a DPSer, that's still a large amount of total damage considering there's only 4-5 DPSers in a party. There are fights in this game that have very tough DPS checks and every ounce of DPS helps.
No, there's nothing inherantly wrong with having lots of Parry if the parry was -free-. But by stacking Parry you're giving up Crit or Det and thus reducing your damage output. Parry scales incredibly poorly and you need a huge amount of it to see even a few percent of increased parry chance. And when you consider 5% parry chance is less than 1% total mitigation against physical stuff only, you have to realise that Crit/Det is just the better choice.
I can understand coming from a tanking background that the desire to be as tough as possible is there, but FFXIV is different - here the ideal tank gets tough -enough- and then does more damage. Paladins are encouraged to swap to sword oath for more dps as often as possible as long as their healer can take it, and that -20% damage taken that you give up from not having Shield Oath is worth far more than any amount of parry stacking.
There's also the factor of the combat table. The way FFXIV calculates hits is a multiple roll system. First it checks if you dodge/evade. Then it checks if the enemy crits. If the enemy DOESNT crit, then it rolls a block chance check. If it doesnt block only then does Parry get checked for, so 30% parry chance doesnt mean 30% of incoming hits are parried, it means 30% of the htis that arent Crits, Blocks or Evades get parried. For paladins with decent block chance this reduces the effectiveness of Parry far more than Warriors/DRKs.
It sounds like you arent going to believe people though without understanding just how important tank damage is in the game. I'm not sure how we can get that across without having seen it in the flesh. We're in a tanking meta where tanks are expected to generally wear slaying accessories rather than Fending ones, tank outside of their tank stance as much as possible, and contribute as much DPS to a party as humanly possible, at the expense of mitigation. Tank damage is generally quite minor outside of scripted big tankbusters which are dealt with via reliable cooldowns and not RNG parry. You can't not pop a cooldown on Thordan's Heavenly Heel because you hope you'll Parry it, you need to ensure you have reliable mitigation. Parrying it is a bonus.
Maybe if parry gave a HUGE amount of bonus chance to parry for each point then it might be worth it on some encounters. But as it is, a tank who stacks parry might take maybe 2% less damage than a tank that stacks pure dps stats but put out 3-4% less dps. That's a no brainer decision.