Seems like this is true for not just code but for all content being generated? Albeit for code it’s more well-defined, but the fork / lock mechanism works for a lot more problem domains.

That would seem intuitively true; it certainly applies to written language, where a clause could go off in another direction, but at other positions the correct grammar/syntax is unambiguous.

thinking - well if we think of lock as happening in a narrative, then I think we can see there can be points where "everything you know is wrong" which essentially allows you to go back into a sort of fork mode and work towards another lock.

Completely artistic creation, creating something that does not exist and that cannot produce things out of itself, means that locking can be more diffuse, not as settled.