- 🇳🇿New Zealand quietone
I tested this on Drupal 10.1.x, standard install. I created a custom block and confirmed I could tick 'Create new revision and made a new revision of my test block. I enabled content moderation and was still able to tick the box to create a new revision.
I then configured content moderation so that custom blocks were included in the editorial workflow. When editing my custom block the 'Create new revision' was greyed out. There is also a nice message "Revisions must be required when moderation is enabled." So this appears to be working as designed and is the solution suggested in #3.
Therefor, I am closing this as outdated.