Modern "Anti Viruses"

Can we talk about anti viruses on windows these days? I would say that personally I'm quite experienced with hardware and know what I'm doing - the usual, with a little help here and there, but all my less tech savvier gamer friends swear that they need anti viruses on their computers and are very stubborn about them, I say that they are unnecessary and not needed if you're an avid computer user and windows' built in anti virus is just fine.

I'm quite conflicted, I want your opinions on this topic, what's up with them these days because I just don't think it's necessary and think that if you use them then you're the product.

Thanks!