I mean ... MAYBE but that leads to the question about legendary Pokémon and their evolution lines which honestly I find a lil dumb. Like do we need Cosmoem or could we just do Cosmog? Do we need Meltan AND Melmetal? Do we need type:Null or would we just skip to Silvally?
In my opinion, you could probably do reasonable cuts and lower it to 13 or even 10 if you put all the Tapu together which by that point it would probably be quicker.
I mean I started the convo bout gen 6 but gen 7 is SOOOOO far from now its not really worth contemplating even now.