Who says Linux viruses are more common than Windows viruses? That just sounds patently false. Why would someone have more incentive to do that? The point of a virus is to infect a computer. Why would someone spend hours developing a virus for a desktop operating system that only comprises a mere 1.2% of the market share?

i think you have it the other way around. usually windows is more prone to/attacks than linux. for a program to be installed system-wise, or a program to make system changes it has to have sudo privileges, and you would definitely be prompted for a password then.

but if you want people you share your files to be protected, you can by all means use an antivirus.

Yes. And even then you're filtering windows viruses. Nothing that could or would run on the server or even in any client that isn't an ancient version of outlook.

Those seem to have pretty much disappeared in the last decade of not before. No vulnerable systems, no infections. No infections, no viruses being sent. There is still potential for scanning somewhere but intrusion detection and spam filtering is more realistic than viruses.