You can literally look up my lodestone. I don't make any effort to hide it. I haven't bothered raiding this expansion, but I've kept up with the strats and clears of my friends so I am familiar with them.
PLD gets a burst of healing once every 60 sec. It's 8 actions (4 Holy Spirit, 1 Confiteor, 3 Blade combo spells) at 400 potency each, for 3200 potency in total. PLD can't casually dump gauge on Sheltron like other tanks can freely use their defensive buttons on cooldown, because PLD currently has to stock 100 gauge to Sheltron+Intervention for every tankbuster. But you can probably figure at least one Sheltron per minute as an average over the course of the fight? So that's another 1000 potency, for ~4200 potency per minute (actually over 1 minute due to GCD timings but whatever!) Almost all of that healing comes in one chain of healing, rather than spread throughout the minute.
Compared to WAR, WAR executes a Storm's Path combo at least four times per minute - figure 2.4 GCD gets you 25 GCDs per minute, 4 of which are used on your IR combo, 6 of which probably get used maintaining Storm's Eye buff, and then you'll have occasional Fell Cleave or IC uses here and there to avoid capping gauge/Infuriate charges. It will fluctuate, but 4 Storm's Paths per minute is fairly consistent. That's 1000 potency of healing, at a speed of roughly 2-3x longer than a standard regen. Assuming you can use it on cooldown or nearly so according to fight script, you can use Bloodwhetting twice in that minute, each time netting 1200 potency from healing and an additional 400 potency from shields. We are, right now, at 4200 total healing/shielding potency for the minute. But wait, there's more! Equilibrium is also a 60 second cooldown, worth 1200p instant healing and another 1000p over 15 sec as a regen. You can add in a Thrill of Battle (effectively a 20% maxHP heal, plus a healing received amp that applies to the WAR's own effects) every other minute, if you wanted to. PLD has healed for a potential 5200 potency in one minute (assuming two Sheltron uses, not guaranteed), while WAR popped off for 7400 potency in that same timeframe (also assuming two Bloodwhetting uses, not guaranteed.)
It's somewhat similar for the other tanks. GNB pops a 200+200 heal+shield on their combo second step, gets 1200p regen from Aurora (two charges, each 60 sec timer), and gets a 900p excog effect from Heart of Corundum, up to twice per minute. DRK has the lowest healing of the tanks, largely relegated to their combo heal (which is 340p) at least as far as raids go (Abyssal Drain is negligible in raids), but has the highest uptime for general mitigation due to Oblation charges, and TBN is TBN. I don't really feel like doing the math on how many combo pops those classes get per minute, but I do know that the numbers were crunched a long time ago and PLD was on the bottom.
It's weird... it's almost like PLD is just missing a whole-ass tool or benefit that the other tanks have. I mean, technically wings gives you 100% block for its duration? If you wanted to do literally 0 DPS for 18 sec, I guess. And you don't have to move at all for 18 sec. There's more to it than just raw healing potency, WAR mitigates a bit less than PLD in exchange for healing more. But even accounting for that, PLD is still behind everyone else - and that's not even factoring in block not functioning on the bleeds they added to tankbusters and raidwides with Abyssos, which puts them even farther behind (hence the gimmicky Sheltron+Intervention plays to account for this, which is why you have to have 100 gauge ready for the tankbusters.)
Guess what? Giving them Clemency on a roughly 25-30 sec cooldown (so, around as long as it takes to build 50 gauge, give or take a bit) would completely fix this. It would add 1000-2000p of healing per minute, subject to gauge management and uptime. Alternatively, they could just add something like 200p of healing or shielding to Royal Authority (or, again, it could go onto Atonement instead, resulting in no sustain from the regular combo but a burst of sustain when it's time to dump Atonement charges.) But I favor a solution that turns a currently useless button into a functional button.
As I've said this whole time, taking Sheltron off the gauge and making it a flat cooldown (probably 25s since that's the same as everyone else), making Clemency oGCD and putting it on the gauge completely fixes PLD's issues with durability compared to the other tanks - assuming, of course, that Sheltron will also affect bleeds. It turns a currently near-useless and iconic ability into one that will be effective and see regular use, and does so without meaningfully harming the class's ability to solo content.
I feel like you're just arguing for the sake of arguing at this point, rather than actually considering the impacts of what's being suggested. It's very tiresome.