I am inclined to agree in principle… however, it might be alright if, like certain other professions already in, the janitor works on regular worker stuff when there’s no cleaning/recycling/whatever to be done. This way, it’s sort of as though they’re just workers that also do clean-up, but you never get everybody focusing on clean-up and neglecting tree-cutting and building duties.
However, I’m still not too sure. In the end, I do think having this be worker jobs sounds better to me, with improved AI so that no job gets neglected for too long (unlike now, where certain jobs sometimes don’t seem to get done at all).