1. AV solutions do in fact offer a lot of protection.
2. You will reduce you attack surface a lot more by not installing Flash, Java, and using an ad-blocker than not using AV.
Do they, though? Everything I've read over the past 5 years has claimed an 80-90% miss rate. On the other hand, often the first sign I see of an infection is that the virus scanner is disabled, so I suppose it acts as a kind of canary, in that sense.
I can't really argue with you if just going to make up stats... I have been helping non-tech savvy family, friends, and co-workers for over 25 years. The ones who didn't have AV installed or let the one that came with the PC expire had a almost 100% infection rate. Once I installed a good AV product infection issues with most of them was not an issue again. Yes, nothing stops stupidity 100%.
25 years ago, I'd be right with you. 15 years ago, too. Since then? I think your anecdata are outdated. Things just aren't going to be caught by signature-based scanning anymore. In terms of automated detection, the bad guys won. "Good" AV detection, if there is such a thing these days, are the tiny vendors that infections aren't designed specifically to fight against. All the big names get disabled, or otherwise rendered non-functional.
I don't agree with you on (1), so I think we need data.
(2) is creating an entirely different argument from blue sky. You're putting words in my mouth.
I support installing ad-blockers to reduce attack surface.
Removing Flash and Java is more nuanced. Most non-advanced users expect Flash sites to work and many non-advanced users need Java sites to work (e.g. enterprise internal crap). I think click-to-play is a decent mitigation here that non-advanced users can understand.
Maybe disabling Java is okay, so long as they really do not need it for anything. Disabling Flash is a harder sell.
Well in my experience as I mentioned in another comment is regular users with no AV solution will get infected almost 100% of the time in a short period of time. The same users with a good AV product I usually don't have to deal with them again. I have no idea how anyone couldn't agree AV solutions have a use.
I didn't put any words into your mouth but was just pointing out better things to do to reduce your attack surface than not installing AV. Java is dead and I can't recall any site needed to use in years that requires it. Flash doesn't need to be installed standalone at all anymore and shouldn't be. When a site requires Flash I fire up Chrome which has Flash built-in and is of course way more secure.
AV does have limited use for advanced users... I have gone back and forth between having a 3rd-party AV solution installed over the years. I have a high end PC and the product I use has little impact resource wise so why thinking is why not?