I found 2 sources claiming RW has a 9'4'' standing reach but does anyone have anything concrete or other sources.
Standing reach is not mentioned enough, if ever, when people are discussing players and it should be brought up.... especially with big men.
In this video, P3 Sports Science shows a spider chart which includes standing reach. It didn't show the height, but it stated he was in the 80% when compared to other NBA centers. That means he has a higher standing reach higher than 80% of other NBA centers. His max vertical was about 100%.
Mr. Leidersdorf points to a couple of really interesting measures:
1) Acceleration of the knee joints in extension 78th percentile measured against all NBA athletes (i.e., not just centers). A man with a shorter limb can be expected to accelerate the knees quicker, all other things being equal; in the case of Mr. Williams, you combine his acceleration with his length and you have somebody who really gets up there, and qvickly
2) On the spider chart he appears to be at somewhere north of 90% for lateral drive - compared to all NBA centers, and, again, combining that with his length gives him an extraordinary skillset for playing NBA defense. If he can get enough court time and has the mental gifts to match the physical ones, he could be one of the top defenders in the league.
I notice, by the way, that two of P3ís clients are Gordon Hayward and Jaylen Brown (of course Jaylen is!).