sir_isOanswered grow question 3 years ago I think that's mostly temperature and humidity related, tbh.
Imo, super happy plants have basically leaves with as much area exposed to light as possible and sort of orthogonal to the light direction, you know, like completely facing it, but sort of flat in that respect.
I had a bunch of seedlings do the praying thing, all of them almost exactly the same recently (about 30 of them), there should be photos of them in one of the earlier weeks in my "randoms I cooked diary" and I could only conclude it's humidity related (or maybe soil) because the air was super dry, but it wasn't very hot, and it's outdoor, they had good light. Maybe the plant bunching to preserve moisture...not sure.
Shit, maybe it's even excessive light relatively, so it tries to expose a smaller area to the light.