Apologies. This turned out longer than expected and might give you an existential crisis, but it's an interesting thought.
Everything is dependent on the context of the story you're telling. Theoretically, both of those things you mentioned are temporary because we will all die eventually (Yikes. Really brought the mood down there.). It's impossible to be a dictator for life, because everyone's life has a finite amount of time. (Sorry again...) But it depends on the context of the story being told, because most stories (understandably) don't take place over the course of an entire millennia.
However, having undergone this whole 'watching every Dramatica-analysed movie' challenge thing, I'm not sure 'temporarily' is an entirely suitable word for this type, either. I'm finding stories with OS Concerns of Being fit into two different contexts, and it's that context that defines what kind of 'being' you're actually looking at:
- stories focusing on people pretending to be something they're not (Miss Pettigrew Lives for a Day; Down and Out in Beverly Hills; Florence Foster Jenkins; Tootsie)
- stories focusing on people trying to live up to (or be) what is expected of them (Black Swan; The Devil Wears Prada; La La Land; Whiplash; The King's Speech)
Here, you can see that both of your examples fit neatly into one of these types. 'Being a Dictator for Life' is Type 1 (because a Dictator is a created persona), and 'Being a Father' is Type 2 (because there are expectations to live up to). It's the context that provides the definition. Similarly, consequences of Being have two contexts of their own:
- stories where characters pretend to be okay under oppressive or unwanted conditions (Star Wars; Grave of the Fireflies; The Imitation Game; Some Like It Hot)
- stories where characters have to live in conditions expected of them (The Producers; Bull Durham)
Obviously, it depends on the contexts of the stories in question, but there are two consistent definitions of this type in both goal and consequence which are either 'temporarily adopting a persona' or 'fitting into an environment of some kind'. Stories of this type usually explore both in some regard, but one takes priority over the other. Just an interesting little thing I noticed.
I haven't looked at Being in terms of MC/IC/RS, but I imagine it will be something similar. I'd be interested in seeing if other types have similar 'contextual subgenres'.