Yes, this may be due to the Photoshop version. However, there is a tool with which you can convert all of these ABR’s into an ABR format readable by Krita, so far. Only ABR’s with copy protection, and damaged ABR’s cannot be converted.
Unfortunately it is no longer officially available for download, but you can still find it on Archive DOT Org, or download it from my cloud.
If you download it from my cloud, you will find there the installable version of abrMate (setup file), as well as the portable version of abrMate in a ZIP and a 7ZIP archive, as well as a folder containing the portable version with all associated files, which would have to be downloaded completely.
A copy of the former website of abrMate in PDF, PNG, and HTML format is also stored there.
Direct download from Archive.org
Michelist