I don't think Williams will be there at 22. DX hasn't updated in a long time but darft already has him at 12. Really hard to find footage on him if you don't have access to watch the games but this one vid has surfaced.
He's a supreme athlete, He's like Stromile Swift but way more advanced/skilled.. he's actually more athletic than Marquese Chriss so I have little doubt he'll be out of range.
Really an ideal platoon partner with Lyles, I can't stress that enough. Even though he's 6'9" he'll easily be able to function as a backup C too. Cheesy but true - Williams would be the Thunder and Lyles the Lightning.
I first saw him 2 summers ago when he was closer to 6'7" and he was jumping out of the gym and appeared to have a near 9' standing reach.
You're probably right though, it's unlikely he'll be in that range. There's alternatives but I suspect none with a ceiling quike like Williams. He could still be growing too.
-Cameron Oliver(Nevada So.) is an interesting alternative. He'd look GREAT next to Rudy IMO, he's built like Millsap but he's got much more bounce which really helps him block shots at a good rate and throw down nasty dunks. (also shooting in the mid 40's from 3 on nice volume this season)
https://www.youtube.com/watch?v=azprOmvJyg0
-Chimezie Metu(USC So.) is also an interesting alternative. He's not the shooter the other 2 are but he's 6'11" long and really exceptionally athletic(and fluid), and I think would look great next to/backing up Gobert eventually.
https://www.youtube.com/watch?v=ONSs1xDveKQ