I use my smartphone for the same things I use my computer. Mainly web browsing if I want to know something/show something. Also for communication. Then comes taking photos or printing tickets or other files directly to my printer without turning on my PC.
Well, I don't read that the woman you know hate men and constantly complain about them not living up to their standards. So I guess there are some steps missing to an Incel. Right now it just seems they have, although very specific, standards on who they wan't to date. If that's not realistic it's their problem and they have to deal with it.
By the way, I'm pretty out of the loop on this Incel thing. I try to keep out of the social media circles who constantly blame the other gender for the things they should do better or have done. Generalizations help nobody
I think the biggest problem would be libraries which are not available in 3.x. I just rewrote a python script some time ago and the syntax changes were pretty easy to change with search and replace.
For browsing I use mostly Youtube and sometimes Soundcloud. Often you can find labels or direct links to downloads/Vinyls.
For actually buying the music I use Bandcamp or Discogs, but I guess it depends on what you play.