It doesn’t matter. The point is that once cleaning becomes too specialized or cumbersome for everyone to just clean up after themselves, the decision to hire dedicated custodial staff or hire an outside firm ought to be made by all the workers involved. And if they decide to hire a custodian, that worker would absolutely get partial ownership of the company along the same terms as the rest of the employees
Janitor used to be a union job with benefits. But they couldn't compete when bosses hire undocumented workers who work at a fraction of the pay, and are easily disposed when they get injured.
cleaning should be an agency/bureau/ministry of the state, so state employees. I don't think any place or organisation outside of people's homes should be able to set their own standards of cleanliness & hygiene or maintainence. This is just my personal view though idk what the correct marxist take on cleaning is.