I know, I just thought I’d explain the general situation to the less savvy people in this forum who will be coming here to get an opinion. Viruses and antiviruses are a domain fraught with superstitions and false beliefs. “Here be dragons”…
Now about the problem you mention, it’s true any app can be a potential point of ingress, especially dangerous if the program has extended privileges.
But on Android this isn’t so important because those antivirus programs don’t run as root. The reason they can’t really do their job on Android is also the reason they can’t do much harm…
It’s mostly on Windows and MacOS they could do some serious harm. That been said, it’s usually better to breach the main OS than to transit through the AV solution, because there are hundreds of AV solutions out there, so targeting one of those will severely limit your ROI (return on investment). Don’t forget virus writers are shrewd businessmen (and -women), the time you wrote a virus for street cred and lolz is over.