Holiday. Yeah, right!
I can't speak for the entire public sector but believe me, with the massive backlog of work that built up when we were under staffed throughout 2020 and the huge pressure we are still under to clear that backlog, on top of all the time critical projects we have running that can't be postponed, it has been anything but a holiday.
Tell me, if the offices are mostly unoccupied then how do you expect those letters to be directed to the right department? We simply advised all our applicants to stop sending snail mail and just send everything electronically instead. It saves time and effort for everyone involved.