The car wash example is interesting, as something I’ve seen and experienced but never thought about in that way.

I wonder how it truly factors into productivity, though. How is productivity measured, and does that measurement capture what is true?

You mention automated car washes as a baseline. I never used those in the past because I figured they’d be rubbish or would scratch the car or whatever. So I’d occasionally wash the car myself, and that’s it. Now that we have manual car washes available, I use them from time to time. They clearly (I assert) do a better job than anything automated. And they do it inside and out.

So I find the comparison interesting, but in need of elaboration.

It's a tautology, if productivity is measured as GDP per worker. Productivity, so defined, is down because each worker is moving money around less, although there may be more workers. Which is the same thing as them being paid less. Question is, if they accept that, and cars still get washed, does it matter?