119 does not inherently do anything you mentioned.

What it does do happens at the level of the Bitcoin tx script, AFAIK (there are descriptions of ideas that work using protocols that use Bitcoin tx script i.e. lightning, but it seems as if the only time CTV is invoked is when the open/close tx's go on-chain)

I don't think there is any _meaningful_ ability to do black/whitelisting, as we have been reliably informed by script gurus that infinite recursion is not possible with CTV. However, better that we verify this for ourselves, Bitcoiners shouldn't want or need gurus IMO