I have tested for some times. Let’s say that there are some times you can connect, but very rare. The GFW doesn’t block the protocol completely. There is a chance you can use for a short time but unreliable.

I have my own openvpn server and the chance of successfully connecting is 50%.

It also depends on what hotels. In some 5 start hotels their network is not filtered by GFW at all so you can connect VPN. Maybe you even don’t need a VPN client to visit google.