You rate AI way higher than you should. Bits designed to play games have been a thing forever, but they just suck. No matter how fancy they still follow patterns and eventually become predictable.
That’s not to say it wouldn’t be good to have the option, but it’s just not the same.
I generally prefer single player games anyway coz I can’t keep up with people who spend all their time online though.
They use spoofing. Apparently incorrectly secured stuff can allow it. The security guys at work were talking about this kind of thing the other week. I don’t fully understand it myself but this website discusses it. https://abnormalsecurity.com/glossary/dmarc