Good point, I should have included that (the linked pgsql-hackers thread have some of this information, at least).

I've observed exactly this behavior on a wide range of hardware / environments, it's not very specific to particular SSDs models (at least not for reads, which is what the blog post was measuring). That's why I showed results from three very different systems.

Some information for the two physical machines:

1) ryzen: Ryzen 9 9900X, RAID0 with 4x Samsung 990 PRO 1TB (in Asus Hyper M.2 Gen5 card)

2) xeon: E5-2699v4, WD Ultrastar DC SN640 960GB (U.3)

I don't know what exactly is backing the SSD storage on the Azure instance.