So the story is that someone came from the future created established bitcoin and went back to the future to get his/her big fat check.
Hell yeah, I would watch that film. Maybe add some apocalyptic scenario at the end like the Paycheck
No, I think Satoshi's "first" future was the apocalyptic world, that's why he travelled back in time. See, in Satoshi's timeline, Bitcoin hadn't been invented before the extremely violent fiat economic collapse. Billions were killed in the nuclear war that followed.
So he traveled back in time to invent bitcoin 30 years before the collapse, creating a new timeline free from the apocalypse of his childhood. Maybe throw some aliens in there just to mix it up.