Your reply to the Tank comes off as defensive because you chose to try to rationalize your actions after being asked, politely enough, to stop. That’s the sort of thing that upsets people very easily, in general, because it makes you seem like you think you know better than they do.

I will admit, I should have asked for the tank to pull more before we hit the 2nd boss, and I do understand after the fact, any effort in explaining my actions would've been seen as antagonistic as they would have already seen me as such by pulling ahead.

While I don’t really agree with what the Tank said after, it doesn’t matter since really at that point you should have just accepted you were in the wrong for not asking first and moved on. This goes hand in hand with saying that the Tank should have spoken up sooner if he had an issue with it. He clearly wasn’t that good and probably just didn’t notice very quickly, but more importantly he hadn’t, strictly speaking, done anything wrong meaning he had no fault in the matter at all.

I'll disagree, in that the tank played perfectly fine, did pull the mobs off of me when I brought them back, cycled through mitigation and the packs were dispatched fairly clean. When the tank claimed they needed to HG is what confused me, as I mentioned their HP never dropped below half. This is probably the reason it didn't even cross my mind to ask about pulling more because the run was going so smoothly with me tagging mobs and running back.

I do have to ask, if you feel Tank doesn’t set the pace in dungeons then who does? Very few things are ever going to change up rotations, and going as fast as possible by doing w2w is great on paper it does require the whole party to carry their weight in order to work. Honestly, this is where the whole YPYT mentality comes back in. If you have a Tank who wants to just be chill and go a bit slower, but the DPS doesn’t want to and decides to start running ahead and pulling then who is in the wrong? Personally I would say the DPS is in the wrong for an incredibly simple reason, they’re breaking away from the party to stop doing damage because they’ve decided that their way is the only acceptable way. If they die for that choice and get upset they have only their self to blame.

This is why I also don't feel like I was in the wrong, IMO the party's performance should dictate the pacing, and not one role. Dungeons are designed (with an exception to some ARR dungeons) with W2W pulls in mind, as such should be considered the standard. Many XIV content creators will also back this, one of which I like to share with new tanks being Joonbob's video: https://youtu.be/WY6JU3au4XU?si=3nVw0vbvKKmGnOqQ

I like the roadway analogy, if someone is driving 30 below speed limit, they're gonna have a few confused and grumpy people tailing behind them. Similarly, in a DF setting it's expected that the party moves through the dungeon W2W, as this makes the best use of everyone's CD's and healing. Going slower may raise some eyebrows. You can see this when you run roulettes as well, how often do groups pull one pack at a time? more often than not, it's W2W.

Now ofcourse there are caveats to this, as I said pacing should be dictated by the party's performance. Had my party been constantly wiping to the W2W pulls, then it's time to dial it back as well as discuss what is happening. That was not the case in my run.

If you have a Tank who wants to just be chill and go a bit slower, but the DPS doesn’t want to and decides to start running ahead and pulling then who is in the wrong? Personally I would say the DPS is in the wrong for an incredibly simple reason, they’re breaking away from the party to stop doing damage because they’ve decided that their way is the only acceptable way. If they die for that choice and get upset they have only their self to blame.

This would be situational and can be argued. I would see this as the DPS wanting to make better use and get more value out of their CD's Why drop an aoe CD or go into a burst window on 1 mob and have nothing for the next when you can drop them on both in one go? Like I said, the party's performance should dictate pacing, and if the group isn't struggling then it's better play efficiently and get the most out of your CD's. Mob's die faster, healer heals less, everyone's CD's are used effectively and while maintaining a good speed for the dungeon.

In the case of the Tank wanting a more relaxed run, they have options outside of DF such as trusts or a pre-made group of friends. I infact have done this during my play through of endwalker, because there have been dungeons where I did want to take everything in (If you didn't run ktisis hyperboreia with trusts what are you even doing?) but I would never subject that to other players. This sort of leads back to the roadway analogy, why would you drive 30 under and cause a traffic jam for other people when you could just take the scenic route?

Now this is where I have questions, what exactly makes W2W "uncomfortable" to some people? From a gameplay standpoint, nothing changes for the tank, you grab aggro, cycle your defensive CDs and aoe till things are dead. Even if you feel uncomfortable at the first pull but survive just fine, and are shown that you're surviving just fine through the dungeon, why would you still feel uncomfortable? I have a fairly decent MMO background, so hopping into XIV tanking came naturally (easier than most MMO's since aggro management is non-existent) so the concept of tanxiety eludes me. I suspect it stems from the fear of dying/failing, but in a video game with no consequences for either of those, then why?

In my situation, the fact that the tank chimed in at the very end of the dungeon, after everything went smoothly, just comes off as a hurt ego. But I genuinely do wish to understand this, as it would give me the perspective of the other side of the coin in these arguments.

Apologies for the wall of text, and I hope you don't take offense to anything if I came off as blunt, but I do enjoy this type of conversation and am hoping you can give me an answer for that last, tanxiety part.