In my understanding it was a timing issue with the UUIDv7 RFC not being finalized before the Postgres 17 feature freeze in early April. Shouldn't be an issue to get this in for Postgres 18, I think.

That would do it. I was mistakenly thinking v7 was done for months/years at this point.

My assumption is that because you can easily do this through software when using UUID and probably a lot do it like this, the pressure of supporting it, is a lot lower than expected.