Phht you don't want to call it data janitor; no-one good will want that title. At least call it Data Integrity Engineer or something reasonably high-status.

This is a hugely important point. Having the right data is most of the battle in the typical project. I'm fortunate to run the data science department at a company with an amazing and supportive team of devs. We work together to make sure that all data is recorded in the most useful way and we talk regularly. Without their support, my models wouldn't be very useful.

Data cleaning always sounded suspicious to me.

As a data engineer I've often billed myself as the Charlie Kelly of data