It is not acceptable. If this is a one-time occurrence the supervisor (or anybody else doing the yelling) should apologize.
When this happens regularly, the supervisor has an anger management problem. You should report it to the graduate chair.
There is usually some way of resolving this “internally”. In the cases I heard, the unit apologized, the ...
An example of an exigent circumstance would be a chemistry professor yelling at grad students who are in imminent danger of harm b/c of improper lab procedure.
If these exigent events happen regularly then the supervisor graduate student relationship is not working and you need to leave.
There are a few definitions of yelling in colloquial American English.
Definition 1: Screaming with anger. This is never ok in a professional relationship; and if it happens regularly, it is a sign of a toxic work environment. This is not a good advisor.
Definition 2: Criticism. For example, if you do a presentation and the advisor has a lot of professional ...
No, it shouldn't be accepted, unless the student has done some serious damage. But that would probably be a rare event.
Solution 1. Find a better advisor (advised)
Solution 2. Yell back (not advised)
Solution 3. Complain to a higher authority (conditionally advised)
Solution 4. If the benefits of working with this idiot advisor outweigh the pain, force ...
While I broadly agree that, for most people, introversion or shyness shouldn't be a reason to avoid all meetings, I think you're focussing on the wrong thing. The rules for your course are what they are, and from your description of the situation it doesn't sound like they're going to change.
What you should focus on instead is that here is an opportunity ...
Making judgements about other's reasons and intentions isn't a positive trait. Trying to coerce people into changing their decisions is even worse.
While I'm a big advocate of having shy (introverted, say) people learn how to come out and act in public without denying who and what they are, external coercion isn't going to "solve" any problems for ...
Is university not the place where people should overcome such personal
No. University is the place where you can work to obtain a degree or other higher qualification. While for many it's an opportunity (expected or not) to grow as a person, this isn't a pre-requisite for earning a degree.
And I hate online meetings, I think the world is split ...
The purpose of any assessment or exercise is to learn knowledge and skills that are associated with the degree/module program. To the best extent possible, the assessement should base its grade on ability in those skills/items of knowledge alone. In pedogogical terms, we call this "constructive alignment".
A person with either a mental health issue ...
In addition to other good answers...
Let's think calmly about this: in what possible circumstances should any person tolerate abusive behavior?
Ok, well, hopefully, as few as possible.
(Yes, yelling is obviously abusive, if there were any doubt. Duh.)
But, yeah, sometimes a person is stuck in a situation, and for various reasons puts up with abuse.
The point ...