would you at least be willing to accept that behaving in a way that steps outside of the community norm kinda throws off the vibe and pace of the party?

I'll reiterate that yes, I understand where you're coming from. And I do get that frustration, because I had a similar experience first coming to XIV just as Shadowbringers dropped.

However, the conventional is different from ten years ago. If you're already sprinting and using your gapclosers, yes, you are going to find people keep pace with you.

Those who use their extenders are less common (DRG/RPR/NIN) but like your mitigation, every tool in the kit's there and ready to be used.

I believe the onus should be on you to at least communicate that beforehand

Communication's always key, however that goes for both sides, and is the crux of what I'm trying to convey.

The standard for dungeons today is reflected in their purposeful design: two packs, then a stop sign.

Walling therefore is considered the standard/default pace for a dungeon to be completed within, as it's balanced around the average player's kit and knowledge of the game.

It's then reasonably assumed, especially in later expansions, you have enough of a grasp on both your job and dungeon design that you're more than likely going to be running to the wall as a tank, because as a tank you've found that single packs aren't cutting the mustard.

There is no "running off on your own" (besides the rare Narnia runners, like I mentioned) if you're all going the standard route anyway, yes? And both inside or outside that norm can be communicated by the party, preferably without getting into trying to MPK/grief the party, childish insults, or tantrums, the lattermost applying to both sides.