Security works in layers. Say you have a security guard right? Well, a security guard can actually be a HUGE vulnerability in your company if he's bribed to help during the theft.
That means we should get rid of all security guards because it's possible for them to be corrupted, right?
nah. not because they are corrupted but because they are blind. do you really need that blind security guard at your front door who is molesting your friends and only keeping the really obvious stupid thieves out when on the other hand you have a dozen backdoors and windows open?
This blind guy kinda helps:
But seriously, are you really that naive? That's like saying a firewall is insecure because technically once you get access to it, you can see ALL the rules on it to find all the weak points of access on the network.
Sure, it's possible that some of the AV software has escalation vulnerability, but really, in today's world, so fucking what? Cryptolocker doesn't give a shit rather you're root or not. The only AV's security vulnerability that'd actually scare me is enterprise AV with it's ability to deploy to multiple workstations in a domain network.