Using Linux you are motivated to know how the system works so if you have enough open mind for this you will naturally learn to think before you do anything in the system. So an antivirus is unnecessary, the best antivirus is the user. In addition the vast majority of programs that are installed are from repositories so it is very difficult to be infected when installing any of them. Keep the browsers and the system up to date think that is enough.
Exactly. Many bug and security fixes are backported to older kernels in the form of "point releases" (I do not know if that is the correct expression).
I don't ever never used any any virus-program in Linus and I went to every page where maybe is something harmful and downloaded s**t and still nothing.
short/harsh/rude/pathetic answer: by using linux you will not turn into a super hero over night or even after 40-50 odd years, but you are welcome to try any color underwear you wish to wear on top of your pants, and also you need to get your own super fu fu foo foo powers and mask to protect your identity. period. polite answer: linux is not as popular as windows OS, and people never bother to pay attention to secure and harden it. its distribution share as desktop OS is very low. so virus developer doesn't find it financially attractive or motivated to design virus/malware/rootkits/trojans/worms for linux desktops installation. and servers are mostly heavily guarded both using OS/Filesystem intrusion detection/prevention system and network intrustion detection/prevention system and also they are regularly backed up and the OS footprint is generally small to be infected, and system admins are pretty well experienced and most of them have in-depth knowledge. so unless there is an ulterior motive and has a premium price/prize value no vx developer would ever like to waste their time on developing virus for linux, its like necro porn star. you gotta be beyond anything if you design a virus which infects linux machine. but if too many people rapidly adopt linux as desktop OS and not just server OS alone sitting inside a chilled room 4 degree centigrade, then companies may and will hire dedicated vx developers to design virus such that it can as well infect your linux machine. because there is a financial interest here. since its all about the money, there is no money here. hence the second period.
Wait a minute. Is GNU/Linux not popular? Android using a GNU/Linux kernel, your router probably some kind of GNU/Linux and many other devices like TV or headphones, too. Yes if you take only desktop GNU/Linux isn't so popular but take servers or supercomputers and you see another picture. I think the main problem is pre-installed OS. How many computers in a market stack with this Windows staff and how many of them is GNU/Linux? I don't know how about another countries and places but in my case I don't see GNU/Linux and this is exotic things for people here. IMO antiviruses is a part of this people. They wanna a security label, a program who you pay for and you thinks "that's all folks, I am totally secure now." Secure staff isn't easy and GNU/Linux is a system who IMO by design can teach you something new. Developers works on close CVE as fast as they can. Windows 10 for example force people to update and this make me uncomfortable but I understood why they doing that and why you can't get a modern version of Windows without an antivirus. In case of GNU/Linux you don't need an antivirus because two: your repository and updates. The repo prevent untasted software and updates closes vulnerabilities. With apps like Firejail I don't see any reason to use an antivirus. What can it do? Even if this prevent 99% of malware, this 1% can destroy your work. Isolation make more sense here, antiviruses for me is no way at all.