And a follow-up, "Avoid Non-Microsoft Antivirus Software", https://news.ycombinator.com/item?id=13489100
I believe there have been academic studies on the non-effectiveness of antivirus software, but I can't find them. (If others can, I'd like to read them.) I find the argument that antivirus software increases attack surface compelling because it's third-party software that tries to get into everything. This is not the '90s anymore; all of the big players care about security. I think that the engineers at Microsoft, Google, Apple and Firefox are more qualified to secure their own software than outside vendors are.