I’ve watched the download speed drop for much of the daytime but I’m not sure that’s the bottleneck, it’s further up the line where servers are overloaded with requests to serve up web pages & are limited by the size of their connection with the network etc.
Youtube are making it difficult for live streamers because of the bandwidth constraints.
Some of the large streaming networks (Amazon/Netflix) seem to have dropped the resolution which makes sense as perhaps most don’t need a 4K picture feed for everything.