I’ve had a bit more of a think about it. As a guide:
-If the only way you can show you’re “good” at your “job”, you don’t have a job, you’re just part of a pyramid scheme, and you must “dress well” with a long sleeved shirt that fits well and a tie.
-If you have a job where your work is what actually counts, nobody gives a toss.
(FWIW, I can dress well, have had a job in a mid to upmarket men’s clothes shop, I just generally can’t be arsed for work, and like T shirts when I’m not at work. And those different fits of shirt up there are just that, different cuts. Neither is right or wrong, and I can think of plenty of people who would look ridiculous in a tight fitting shirt.)