During a pandemic which has forced a huge number of people to stay at home and is currently crashing the economy and costing hundreds of lives per day, it could help to be a little more sympathetic to measures like this. They might not be perfect, because everyone is having to react so quickly to what is going on, but we can appreciate that this is not a normal event and the vast majority of companies have never planned for it (random ISPs, for example). If this article [1] from Netflix is to be believed, 4K uses five times the bandwidth of HD, and is surely an easy target for something that can be traded off while not affecting people's moral wellbeing too much.
Suffering a video quality decrease would seem a small price to pay for not causing further problems, and perhaps once this is all over, or at least we've stopped flying by the seats of our pants, we can see if people should receive refunds of a few dollars a month.