I used to laugh it off when my friend did this, but he learned quick that people aren’t willing to wait 2-3 seconds between pulls anymore.
It became a problem when he was the one getting angry all the time when someone pulled, accident or not. He stopped tanking, but to date I take this to be his decision, not a failing on a part of the community.
There are even times in FFXIV, which is very sterile in its dungeons, where someone pulling ahead can be annoying. Generally, though, people aren’t doing it to be cheeky or malicious - we’re all working toward the same goal.
If the group wipes because one of these pulls, it is absolutely an error. The problem is the idea that someone other than a tank pulling is inherently wrong. No one is infallible, and the tank is one member of 5. “DPS are replaceable” is not a civil approach to the game. It also doesn’t apply in M+, really.
There have been times even in pugs where I was expected to pull to get mobs together for a specific pull strategy. Usually because of dungeon layout, you don’t see this sort of thing in Sanguine Depths, for example, but you DO in Halls of Atonement which I mentioned earlier.
I also frequently tell my friends to pull things for me, so I don’t have to play the frantic targeting game in a bigger pull. This is a communication thing, but pugs have to make do with the communication which is feasible for them.