I think that good writing is one of those things that people don’t consciously realise. Just like actually good UI.

You do it because you care about it. It's an instance of "be the change you want to see in the world".

It would help motivation to have some allies though.

The moment I switched from selling code to selling text people started rewarding me for it.

How do you measure lip service vs not?

lip service - in interviews and onboarding talking about how they value documentation

not - in actual work no time put aside for actually writing documentation.

Somewhere in the middle, my place definitely values good documentation. I’ve gotten kudos for it and I’ve had my manager bemoan poor docs written by other engineers as a sort of “doesn’t meet expectations” signal.

We don’t explicitly put aside time for it, but it’s expected as part of normal work. Though mostly for upfront design. Less often for after the fact design.