Sampson was an absolute MONSTER coming out of college. I remember Red did everything he could to try to get Sampson to come out of high school straight to the NBA in 1980 because the Celtics had the #1 pick.
That's how good Auerbach valued him. Of course, Red traded that #1 pick for Parish and the right to select McHale, so everything turned out okay, but originally, if Sampson came out, Red valued an 18 year old Sampson more than 4 year veteran Parish and a 22 year old McHale coming out of college.
After Sampson got hurt, he really wasn't the same ever again. Bone on bone with no cartilage is just not something you can play with and be decent, nevermind elite, in the NBA.
Also, wings and guards weren't not in the same stratosphere, when it came to value, as multi-skilled big men in the early 80's. The game revolved around the big man. So using 2020's positional values to judge MJ as a prospect versus bigs like Hakeem and Sampson is just 1000% wrong because that's not how NBA GMs at the time valued players.
Lastly, if all you got to judge Sampson is stats, you'll really never grasp just how good Sampson was before that injury. But, given where this stat driven analysis is coming from(the site not the poster here), color me unsurprised. That site tends to has massive flaws in their analysis because it only puts stats in their algorithms and then finds vids to match the storyline they try to tell in their analysis.
Moses wasn't that dominant. Bird was an off the ball player. Ralph Sampson wasn't that good. Not knowing the reason the 2002 Bucks fell apart was due to the cancerous addition of Anthony Mason. Time and time again, that site is just flat out WRONG.