Gigabit to public VPN providers? No chance. I have experience with ExpressVPN and NordVPN. Both are "fast" compared to others. PC with i7/i9/Ryzen CPU... doesn't matter. 180-220Mbps is what you usually get.
Public meaning not self managed? Because these are not open to the "public", only to subscribers of the service. But I understand there are many users connecting to the same servers at the same time.
I guess unless I can find a VPN provider that can do more than 250 Mbps then the RT-AX88U would be sufficient.
Does anyone know of a provider that does more than 250 Mbps?