The target user base is much smaller. Most viruses are spread through user error and server administrators are far more competent than a typical OS user. Also, typical server exploits lead to exposing credentials rather than spreading viruses.

I find the Linux ecosystem has far better updating mechanisms than Windows and it doesn’t have as much backwards compatibility cruft as Windows. That and the open source nature I think is better at having exploits uncovered. I’m not saying Linux is perfectly secure, but that it’s more secure than Windows. But I think the biggest reason it’s less likely to get viruses is just that it’s a smaller target and that hackers aren’t spending as much time trying to attack it, plus the users are more tech savvy meaning any attacks will be less lucrative.

They’re super rare. I’ve not gotten one once in decades, whereas I’ve encountered countless viruses on Windows. Linux is more secure, but also it’s just a smaller target. Best way to avoid viruses is to use an OS nobody else wants to use *taps head