I don't know that it really changed. I think people saw flashes as a 19 year old and got really excited. Physically he is not special. Athletically he is not special. Technically he is not special. I believe that everyone thinks he can be really good, but no one is seeing a kid who is a generational talent.
Even compared to last year. He is not as physically impressive as Mehki Becton. He is not as athletic as Tristan Wirfs. He is not as refined as Jedrick Wills.
EDIT: And none of this is to dimish him, but it lends to him being taken in a similar range as those three last year than a top 5 player.