This procedure was meant for the external backup disk instead of the internal macOS SSD. The macOS SSD needed to be left untouched.
In my previous reply I mentioned this should be done on the large hard drive (the 2TB Seagate Slim, if I recall correctly). The purpose was to prepare the 2TB drive to act as both a backup disk (in one volume) and a storage disk (in the other volume).
The APFS Volumes article was meant to teach the basics of APFS volumes, not to follow those steps exactly. It was necessary to tailor those steps to suit your unique requirements.
Because you are not telling me what exactly you did, I assume you created one additional volume in the main macOS SSD, called it “home”, and followed the procedure to move the home folder to the new APFS volume. If so, the procedure should have succeeded. To be sure, doing this is actually a good idea if the main disk is quite large.
Because I’m not sure what could have gone wrong, I will need to perform the same procedure on a backup disk and see if I can reproduce the issue you’re reporting.