All depressing news.

I'm afraid we've reached the stage now when all such organisations should follow suit. If not, they will inevitably leave the impression that they are not being responsible.
Of course, they may well have thought things through and the local risk, especially at the moment, may be non existent or minimal. However, the perception by others may not be the same.

As regards sessions, they can maybe continue for a while. I don't see an issue of a few friends getting together for a tune if they take care but, preferably, it should be a more low key affair. Not something which is advertised far and wide or on an "official" basis.

There's talk about closing pubs and keeping restaurants open but the distinction between the two can be quite blurred these days. You can eat, drink, and socialise in both.
There are some quiet and roomy bars and very busy bustling restaurants.
Personally, I would be very choosy these days(I am mostly, anyway) and standing ten deep at the bar in a Wetherspoons or similar would be out of the question.