On top of that, sick days are much less frequent now I daresay.
But to be honest, that's fine/expected? There's a quite large range where I might not feel up to the commute/office (or not want to cough and sneeze at people - aside, I bet that's going to be more stigmatised in the near future) but up to doing what I can from the comfort of home where it doesn't matter that I'm curled up unshowered or whatever.
I did that a couple of times even when I went in to the office five days a week - gives me something to do other than lying in bed feeling sorry for myself or doing something and feeling guilty that it's not work, and gives my employer a bit of output even if it is less than 100% (which isn't the alternative, 0 is).
Sort of like how flu cases went down during the pandemic — with less interaction from abroad less germs are transmitted.
So talk to them about those expectations. Let them know that you won't respond outside of X hours, etc.
There are times when your most important work is being available. Maybe less than some managers seem to think, but it does happen. I can go make myself a complicated snack or step outside to do some yard maintenance for half an hour here and there and still be back to my desk in 5 minutes if someone actually needs me for something. At lunch time you can usually stretch that to 15 minutes, which opens up a lot of options for errands.