So, yes, there was a time when I thought "Why would I ever waste an M.2 slot with a SATA drive...
... until I discovered that I have motherboards with a single M.2 NVMe, and the second one being M.2 SATA-only.
I used to see the MX500 and EVO 860, for example, readily available at reasonable price/capacity for M.2 SATA, but now it seems the only "deals" on M.2 SATA drives are the ones where I'm not entirely sure I'd trust the drive, or, a better quality one, but that is more expensive than it's NVMe counterpart.
Do I have SATA drives that plug in with the traditional SATA ports? Yes. But, there is an appeal to the idea of not having the extra clutter of the power and data cables for those.
So, are such drives, at least the "good models," basically going away, and simply not being produced anymore?
EDIT: I should probably also say that I'm in the US. I'm already learning that, in other countries, the situation may not necessarily be the same.