This seems to confuse social stigma and gender bias. Garbage (Bin) men are overwhelmingly male, so too are plumbers, and pest control, sewer-workers and the like. A comment like "good, I didn't want a son that wiped [shit] for a living" would apply to any of these fields, it seems without reference to gender. Quite the opposite, as dealing with such filth actually is something women quite avoid.
Fair enough, that specific statement could indicate a social stigma unrelated to gender. It was, however, common to encounter plenty of skepticism that nursing was a proper profession for a male.
There is at least some biological reasoning behind why sanitation workers are overwhelmingly male, it's a field where physical upper-body strength actually matters.
