Part of this is on developers. Refactoring is fine, but too often it turns into yak-shaving and nothing ships. The approach usually works: refactor in small steps and tie it to a feature so it’s testable and adds value.

Very much this. There's no need (and certainly never time) to add tests to the world or refactor everything. But it's often practical to figure out "I need to make changes "here" and add tests for that section and do whatever cleanup helps for that bit.