The new app only officially supports limited distributions (Debian, Ubuntu, Fedora). The CLI isn’t updated to v4 yet. You can still connect to the VPN by downloading the config files (OpenVPN or Wireguard) and connecting through, e.g., wg-quick protonvpn.com/support/linux-vpn-setup/
It’s weird, because despite not having port forwarding on Linux I’ve never had any problems torrenting.