Port forwarding allows unsolicited connections through the NAT firewall on specific ports, making it possible for devices on the internet to initiate connections and access services on a local device . Basically by turning off port forwarding you improve your privacy and network security at the cost of lower torrenting speed and no remote access.

when you use port forwarding, you're opening yourself up to a lot of malicious activity. Someone could maliciously plant some CP on your hard drive if you have port forwarding enabled.

A lot of people still don't and they use public wifi too. And some people with VPNs are using shitty ones like nord, express or Private internet access or surfshark

Surfshark and nord are owned by the same company and express and PIA are owned by the same company. So PIA isn't trustworthy anymore, their court proven no-logs policy isn't valid anymore because they got bought out since then.

I haven't had that problem when I use proton. Try using secure core with the browser extension.