[Schiendelman]

You most certainly can. I work for a US company where when you're out on (paid, six month) parental leave, your system access is disabled.

They don't do that for normal PTO but it's certainly feasible.

[ghaff]

There are a lot of reasons to cut access for people out for an extended period who may not even come back.

Pretty much no one (outside of maybe something regulated who may mandate two week PTOs for security purposes) is going to do that every time an employee takes PTO. In any case, if I really want to do work I don't even need access to my employer's computers.