For gifts specifically, the giver is supposed to pay the tax.
Everything else you listed is taxed as income (with different rules depending on the source) just like you said. You could also add inheritance (unless special loopholes are used) and proceeds from the sale of illegal narcotics.
The author of this is really twisting the story in his own favor. He leaves out the part where he launched public personal attacks against other faculty and students.
His department did try to work with him so that he could teach his class (which was completely outside his field of expertise, and is therefore against the general policies). They wanted him to co-teach with someone with knowledge in the field, but at that point he had completely ostricisized himself and no one wanted to work with him.
This is absolutely a situation where someone fucked around with a loaded gun, shot themselves in the foot and is now mad at everyone else because they didn’t help him shoot someone else.
That sounds like socialism which is bad because it’s bad. Look what happened in Canada, they didn’t pay animal and worker abusingly low prices and now they don’t have insanely high prices. Without causing these situations they are denying large parts of their population high sustained cortisol levels.
This is why we need to maintain our threats of annexation. We must provide them the stress that their government denies them.
As an American, I think finding the dumbest of us would be hard given the amount of competition.