That is a bad equivalency- I am sure many black couples would struggle the way your parents would struggle due to their genetic makeup.
As for the topic at hand, I think it is fair to say the world class athletes are to a degree genetic freaks- physical and/or mental.
When you get to the QB position, It is way easier to be a genetic freak mentally and succeed with mundane physical skills than it is to be a physical freak with mundane mental skills.
By all physical standards, P. Manning and Rivers should never have made college QB. but both guys are outstanding at reading and reacting quickly as well as instant recall of past film sessions while ducking monsters.
On the other hand, scores of physical freaks of nature bomb out of the league every year at QB because they just dont have the mind for it.
As for Williams point, I dont know the numbers, nor do I know the players getting short-changed.... but he may very well have a point if you look at it from the above perspective.
Both of Archie mannings boys were sub-par athletes, both likely played with high talent players that were massively physically superior to them, and if they didnt have an NFL QB as a dad, there is a big chance they never would have had the opportunity to develop- they would have been bounced for stronger, faster guys.
Rivers' dad was a coach... and I bet he started over some better athletes.
From that standpoint, it becomes more who you know than what color you are.
The above examples had double blessings. An in house mentor and someone in power to assure they get the opportunity to succeed.
Someone who can pay for every camp, introduce them to every college coach, open every door and support them as they learn.
At that point it seems family money and notoriety beats color hands down.
WIlliams may have a point that the system being what it is, there may be a ton of black players with the tools to do the job but nobody in power to assure they get a fair development period, nor people that understand how to hone their skills.
Lets be honest, public school coaches can only do so much. they can only mentor so many people.
It seems the lions share of NFL QBs have a laundry list of special camps beginning at youth through college recruitment, and it is few and far between that you get some schlub white or black that *only* did pop warner and high school.