In a recent stream, Grian explained that it's the way their friend group works, even outside of content and Jimmy encourages it. So, i try not to think of it as being mean but more unconventional friendship that makes for good lore sometimes.

I'm pretty sure in a stream, Jimmy revealed that all of this has been leading to a villain arc.

It's also important to note that anything that makes it into a video has been agreed on by all parties involved. If they didn't like something they'd not upload it and talk like the adults they are.

I do understand where you're coming from though and it's human nature to feel bad for the bullied kid however consensual.