after the update to indd 2022 (which some idiot client editor did in the middle of a magazine before saving and thus up-versioning half the files) I have problems with pdf export. Since acrobat/distiller seems not to have been updated at the same time, I assume the problem is with indd.

When exporting for print, indd exports black print as rich black - regardless of the indd settings - when the export to pdf settings /output / convert to destination (profile) is set.
If I export with / convert to destination (preserve numbers) then black is exported correctly. This is obviously bunk.
thw workaround (half a day to find this) is to export with convert to destination (preserve numbers). Caveat all images needed to be converted manually before export, as a specific output profile was necessary.

needless to say everything worked as expected before the 'update'.

Seperation is determined with Acrobat CC preflight ink separations.

I can reproduce the error with a new document, with text cmyk 0 0 0 100 /adobe preset output all blacks accurately /, exported to pdf converted to ISO coated.
With "preserve numbers" the separations in Acrobat are correct, without preserve numbers rich black is exported.

System
AMD Ryzen 9 3900X
RAM 64,0 GB
Windows 10 Pro
Version 21H1
OS build 19043.1348
Windows Feature Experience Pack 120.2212.3920.0

indd 17.0 x64