I'd say he's still no. 1 prospect unless Chytil produce like 40+ pts. I'm not terribly knowledgeable but... Shesyorkin has dominated the 2nd best league for two years now... Chytil had an above-average season in the 3rd most competitive league... his NHL stint was solid but an insufficient sample size. OK, granted, Chytil is nearly four years younger and very well may end up a more well-regarded player but as of now, Shestyorkin has made the last few World Cups and was on the gold medal Olympic team.
I think because Chytil is still 18 and so good, and people so desperately want to see them develop that star, everyone thinks the kid can walk on water. More developed is Shestyorkin... And don't say "it's a measure of likelihood to succeed," because this board ranked Neal Pionk no. 8, behind 3-4 players who are 18-19.