He likely violated the terms of his visa, which is a crime.

“I had to [stay in school]..otherwise I’d get kicked out of the country.” ... “since I already had my undergrad, I could..get an H1-B visa” (not correct, he had no degree in 1995, so he's already on record lying about many aspects of his visa and schooling situation)

"I was legally there, but I was meant to be doing student work," adding to The Post, "I was allowed to do work sort of supporting whatever." You cannot work "supporting whatever" on an F1, exceptions like OPT are restricted to specific programs. Musk has (more than once) admitted to violating the terms of his visa and working illegally.

> Derek Proudian, a board member for the Musks' former internet startup Zip2, which they founded in late 1995, told the Post, "Their immigration status was not what it should be for them to be legally employed running a company in the U.S.," adding, "We don't want our founder being deported."

Musk had no degree in 1995. And it sounds like he was on an F1. If those are both true he was working illegally.

Snopes has a lot more details https://www.snopes.com/fact-check/musk-undocumented-immigran...

>actual felony violations of criminal law that normally result in prison

Has anyone gone to prison for 30 year old visa irregularities? I'd say it's not normal.