It isn't, and immunocompromised employees should meet no resistance when continuing to work from home, but it's unclear that we're at a point in the pandemic (or have been, for many months) where avoiding office work is a meaningful intervention for slowing transmission. We sort of axiomatically assume that avoiding offices must slow the spread, but the epidemiological evidence for it --- for any kind of social distancing --- is very weak (unlike, say, increasing vaccination).

That's not to say those kinds of NPIs weren't very important at earlier phases of the pandemic.