There was an old cartoon they used to show back when they had driver's ed classes in high school. It showed the Disney character, Goofy, as his usual, amiable, goofy self until he got behind the wheel of his car and then he became a raging A-hole.
It's gotten to be like that with the advent of the internet. Feeling safe and unassailable, people tend to turn into a not so nice version of themselves. Some even go several steps further.
The problem is, after doing it for so long, they maintain that persona out into the real world, which explains a lot of things as of late.
All the best,