I had to google it, it sounds selfish when the trouble is caused by many neighbors having their own APs nearby.

Doesn't it enhance to the problem further though? (if yes, then yes, wifi kinda sucks)

not really, as I believe any router that uses more than one channel at once must disable that feature if there are any other APs that are trying to use any of those channels.

Can't speak for anyone else, but that was not my problem.

It uses 2 5Ghz channels and 1 2.4ghz channel.

I bought this one: https://www.amazon.com/gp/product/B0167HG1V6