Does being sued by a debt collector hurt my credit score?

The lawsuit itself, no. What's actually dragging your score down got there long before anyone filed paperwork, the charged-off account sitting on your report, which predates the case entirely.

The bureaus stopped putting civil judgments on standard reports back in 2017, as part of an industry-wide agreement called the National Consumer Assistance Plan. So a new filing doesn't add a fresh mark on top of what's already there. A lot of people assume ignoring the suit somehow protects their credit, but that instinct is backwards. A default judgment, the automatic loss you get for not responding at all, doesn't touch your credit report directly, but it does create an enforceable public record that opens the door to garnishment, and collectors count on defendants not answering.