This is still occurring. I do have a little more information:
This problem also affects the Creator Companion and the VRChat SDK Panel within Unity. The Creator Companion will fail to connect, and the VRChat SDK Panel will show “Loading… “ on the “Builder” tab.
Changing the DNS server (to 1.1.1.1) does not fix it for me, but using a VPN does. Using WiFi instead of Ethernet also fixes the problem, as previously discussed.