I know what they are, what they do, and why they’re theoretically useful. However, none of the public Wi-Fi networks on which I have ever tried to use a VPN has worked when the VPN is enabled. I’ve always had to use the open network and just be really careful.
In the States, I never use public Wi-Fi anymore. I always defer to my 5G connection. But on my trip to England, obviously, I didn’t have that luxury. I even had to completely delete the VPN app to use in-flight free messaging. Not even disabling it worked. It wasn’t until I deleted the app (and the profile) that I could use the in-flight Wi-Fi.
In short, I’ve never found them useful. Is that normal?