Today we streamed part of one of the Japan rides (Former Tsukuba Railway Course). The video was quite poor with frequent pauses. I have not had this happen in a long, long time. I stopped downloading videos a while back because the streaming performance had been very good. I have an Ethernet hookup to the PC and my Internet connection speed to this computer is 400-500 Mbps, so that is not issue.
I don't know if there was a large load on the servers. My ride was done at 4 pm PST (Midnight Greenwich/Zulu), so I would be surprised if there was a big load on the servers. When I clock through current rides, it does not look like a huge number of riders, by I am basically guessing.