This is not a direct answer, but:

1. Uva is the cause of most skin cancer

2. Uvb generates vitamin d and sunburns

3. When uvb is present, you can make sufficient vitamin d quite quickly

This would suggest you would want sunscreen for longer exposures, or with much uva exposure. And could get vitamin d from a briefer exposure pre sunscreen.

I can’t say how completely sunscreen blocks vitamin d however.

Given that sunburn is a response to cellular damage of your skin cells, why would it be the case that the two are de-coupled w/r/t UVA and UVB?

Actually, it seems I was wrong. I thought it was just UVA, but uvb also causes melanoma.

I’d delete the above comment if I could. The main point that you can get vitamin d from short exposure without sunburn is correct, but I was incorrect on the risk. But he fact I was wrong about uvb and melanoma also makes me think I may be incorrect on the risk of uva during periods without uvb.

https://en.wikipedia.org/wiki/Melanoma#UV_radiation

the body makes vitamin D3 when UVB rays hit cholesterol in the skin

sunscreen either blocks, scatters, or absorbs those rays

seems to reason that sunscreen slows down sun burn and vitamin D3 production