Viruses are so 80's. The big money is user information, this is where big companies make a lot of money, like Google Ads. Also Known As Spyware.
Viruses started as a joke, a prank, a way for coders to have fun. Viruses flourished on Microsoft platforms like DOS and Windows because Microsoft never really cared about its customers other than how to sell more and make more money.
MacOS X is a Unix based OS. Unlike Windows, a file cannot do whatever it wants. If it tries to modify your hard disk in any way, outside the home folder, it needs permissions. Permission you give. That makes life, for a virus, seriously hard. Because the goal of a virus is not just to infect your files, that means nothing, it's there to infect your system to infect your OS. To take control of your OS. That's the end goal.
It's not impossible to hack an OS like MacOS X, but Apple is not stupid and, unlike Microsoft, it cares - because safety and reliability is what it sells.
I have owned an iMac for 7 years and I've never had the problems I had with Windows. I see little reason to install a piece of software that will slow down my CPU and offer me zero benefits.
There is no such thing as safety, safety is an illusion. As a matter of fact I have caught viruses on Windows several times using an anti-viruses that was full updated.
If you want real safety, disconnect from the internet and install nothing. This is the only way to be sure.
What seriously annoys me, and one of the big reasons I left Windows for good, was that Microsoft created this culture of "getting a virus is what happens for an OS" like its something normal. It's not normal, it's a serious flaw in the design of the OS, a flaw that survives because customers tolerate it as "normal".
Do not install anti-viruses, you paid for your OS, demand from its publisher to deliver an OS that does what is reasonable to expect to keep you and your files safe. Viruses and malware are unacceptable.