I wonder if Fangraphs used any comps in its model for him other than Hunter Greene. It's pretty much the same stuff from a similar body, and Greene has had one very good MLB season, a couple mediocre ones, a Tommy John, and will never be able to go through an order 3 times despite being the size of a small apartment building.
I'm never optimistic on 2-pitch guys as starters where the winning case requires blowing high fastballs by MLB hitters.