What? It's used by tons of legitimate applications as well. Not only malware benefits from being able to accept connections from the Internet. Games, torrents and other p2p services, etc.
I play a lot of games and I've never had any issues not having UPnP. They got used to working around it. Probably with centralised servers. I never liked the P2P model anyway, dedicated servers are more fun because you can influence the gamemode, add mods etc.
For torrents I don't know... If I were to torrent I would not do it without VPN anyhow.
For torrents I don't know... If I were to torrent I would not do it without VPN anyhow.