If you're doing a P2P related activity over a VPN (or otherwise), port forwarding is very important for improving speed or enabling the service at all. That's because your router blocks incoming traffic from certain ports by default, ports that will be used with a P2P connection. To get around this, you can 'forward' a port that can be used for said P2P activity, letting your router know that the traffic you expect to see from a specific port should be let through.

You can simply leave port forwarding to your personal router, but if you want to stay anonymous while participating in P2P connections, then you'll want to use a VPN service. If a VPN service doesn't utilize port forwarding, then any P2P connections you use will either be straight up impossible, or very slow. For example, you wanted to host a gaming server without giving away your actual IP address, then a VPN with port forwarding is desirable. The same can be said for torrenting.

A few months ago. They said that hosting companies and other providers were refusing to work with them if they continued with it as a feature.

It's just too easy to abuse by bad people using it to host very questionable content. Lots of people then moved to ivpn and then they removed it too, for the same reasons.

Ovpn.com still offers port forwarding however they were recently acquired by a us company which could be a red flag

can’t personally vouch but AirVPN still has PF if you need it.

That's probably fine for pirating stuff, but I hope you have no expectations of privacy. Terrible company.

Airvpn - was the only suitable alternative. I miss mullvad but it works and unlimited port forwarding.

I moved back to Proton. But on Linux I still don't know how to portforward now.

I've only ever had to use port forwarding for gaming servers. In most other cases I've found better options

Can you expand on what you mean by that please?

Got a replacement in mind yet?

Yes, but only on the paid plans

yes, but only if you pay, and the port you get isn't static, so it changes every certain number of minutes, so you need to find or juryrig something to auto update your torrent client to the right port.