Also, it seems a little odd to call some of the technical problems "Bad etiquette". Nobody chooses to have those happen, and often they have limited control over it. That doesn't mean they can't be a problem, but they're not an etiquette issue.
Like so many things in the list, it's not a problem until someone abuses what's reasonable and it becomes one.
Let's say you have a bad mic, you know you have a problem, but you commit to playing a game where it's understood that the tech is crucial to participation. The first time it's a problem, people understand. Three months later, people have asked every week and you can't be bothered to get a $10 headset that would fix the problem, or log on with a different device? As time goes on and you don't solve the problem, eventually it crosses the line from an understable issue to an etiquette problem.
Like everything else on the list, I think that this is highly dependent on the expectations of the group. As a legal technologist I've worked with attorneys and legal assistants continue to struggle with software even when their jobs depend on it. There are people for whom certain technology continues to challenge them. They are not being willfully obstinate, they just can't seem to grok it. Often, but certainly not always, age can play a role.
How patient the rest of the group is and how willing they are to accommodate depends on their existing relationships and there expectations of competency. It is similar to expectations of rules mastery. With my main campaign, the game system, both rules and the game specific GUI for Foundry (Warhammer Fantasy Role Play 4th edition), we all have a lot of patience with each other because it above average in complexity, but I don't think that someone with very low technical proficiency would be a good fit for that campaign.
At the same time, I've been playing with this group for years and if, when we first switched to WFRP, the players struggled with it to the point of it not being fun, we would have switched to another system.
Insists on rolling physical dice when everyone else rolls in the VTT
Also a "goodbye" level offense.
I'm generally on the same page. Barring technical glitches, we all roll in the VTT. Like when we play in person, we all (GM included) roll in the open. Watching other players' rolls keeps us engaged and exited when it is not our turn. This is also why I like VTTs with 3D dice simulation, like Fantasy Grounds or Foundry with the Dice so Nice module. Watching the dice roll and come to a stop before the numbers are shown is just more fun for us than having them immediately posted to chat.
Overly "comfortable" dress when on camera
not an issue in my current online group... mostly because we do voice only. One of the players has VERY limited upload.
Yeah, I just threw that in based on horror stories I've heard and kinda experienced once on work calls. Had a co-worker who had to join an urgent meeting while he was on vacation and on the beach. He forgot to turn of the camera on his phone, but thought he did and wasn't holding it up to his face. We all just saw his nipple for several minutes before someone brought it to his attention as politely as they could.
Engaged in other activities on the computer not related to the game
Only a problem if they're not able to pay attention to the game at the same time. Some do.
My philosophy is that it doesn't bother me if I don't know you are doing it. Meaning, if they are ready on their turn and don't need things constantly repeated to them, I would have no idea unless they told me. I don't like it in in-person games, however. Even if they are still able to pay attention, it bothers me to have someone constantly looking at their phone during in-person games. Maybe its my age, but I don't like people glued to or constantly checking their phones at dinners, while playing board/ttrpg games, or other social events.