Honestly, I couldn't quite simpatize with her. She complains they were giving her too much to do?

Unless you fully understand the effort involved in her reported daily and weekly quotas, you aren't qualified to make an opinion on them. But what might make more sense to you is that LTT currently has a full team dedicated to what she was expected to do by herself.

The biggest issue for me was her reports of a toxic work environment. When she would bring up concerns about her workload, they'd respond by insulting her and threatening her job. She even saw an instance where a coworker felt she was sexually harassed and Linus yelled at and berated her for being an idiot.

My guess is that Linus is the owner and works like one, and wants everyone else to work as much as him.

This is exactly the kind of boss that creates a toxic work environment. A good boss should be respectful of each employee's strengths and limitations and foster an environment where everyone can contribute meaningfully without feeling unduely overburdened.

Yes, Linus is a workaholic. His work ethic is unhealthy. He has publicly acknowledged this on WAN show numerous times. If he expects his employees to work as hard as he does, then he is knowingly fostering an unhealthy work environment.