....
Basically, I think that with many more users, we would see more Windows
users and they would be less secure in their habits. We've already seen
this to some extent with Ubuntu. I don't think it's any more difficult
to write a virus for Linux than for Windows, but the R number for such
a virus, as epidemiologists would put it, would be very much less than
one, so there's no point. No propagation. I think this would change,
but this is of course just an opinion.
Linux servers are running headless in data centers, not on many desktops in comparison. So the desktop set of intrusion vectors are not present on them. Rarely does a human log into them, they're managed and usually installed remotely using ansible, salt, CloudFormation on AWS, etc. Software running on them answers requests at TCP ports, that's what they do.