I agree that it's a bad idea to use "janitor" as a disparaging term, and that was very far away from my intention. If that was what you took away from reading it, then that's more evidence that I didn't do a great job with writing the original draft.
Here's the original paragraph for reference:
Data engineers are the janitors who keep your data clean and flowing. Insights are great, and you need them. But to deliver insights at scale, you need data infrastructure. That’s delivered by data engineering. It’s not as fun to talk about as D3 visualizations and business intelligence dashboards, but it’s every bit as important.