It's not just the US - most of the West has decided over the past week that public gathering bans are over. They were never going to be sustainable forever.
I think the assumption was people would be packed like sardines in protests.
Right, that's happening across the Western world. There are a ton of George Floyd rallies in Europe.
Perhaps public health officials don't like protesting leftists very much. Certainly if they believe the virus is as dangerous as they were saying two or three weeks ago, they mustn't.
Most countries realize they have the hard task of balancing the right to protest, constitutionally protected, versus the need to protect public health.
That's what they were doing a month ago. Government leaders said something along the lines of "you know, you have a right to protest, but protests have severe public health implications so please try to stay home". This week they've been endorsing and often joining the protests; they don't seem to believe public health is a relevant factor anymore.
Police have been breaking up protests all over, for example in Germany and Sweden.