The software equivalent would be if the FSF found some sneaky legalese, and came out with a hostile GPL 5 and simultaneously invalidated all previous versions of the GPL. Thus rendering everyone pre-v5 unable to publish going forward, with the only recourse to “upgrade” to the new version.

It’s sick, and likely not legal, but in the D&D example Hasbro have a much bigger legal team than the people they are trying to bully. So the threat of a potentially expensive lawsuit to force small fish into a legally dubious license.