Is free TotalAV antivirus a scam?

I would uninstall it. It tends to interfere with the computer's operation while providing minimal to no benefit unless you work with Windows files.

http://support.totalav.com/kb/article/152/uninstall-in-mac-osx

Macs & iDevices do not get viruses. (virae?)

What device?

What did this "falsely" report?

Macs can get "malware" - but that's a different story

This used to be totally free (written by a member here in ASC) but now is 30-day free trial

Malwarebytes | Malwarebytes for Mac

https://www.malwarebytes.com/mac/

editADDED

Looks like I was composing while everyone commented 😊

So? What did it find? Or should we guess?

All kinds of stuff? What prompted to you to first download the useless app?

I suggest you not pay for that crapware.

You are welcome.