Well, actually …
In this day & age, a football player has no shot at the NFL without substantial support from home for many years, from the age of about 6, right through their first NFL contract. The days of the unschooled farm kid being taught to hold a football and run toward the goalposts are long over.
We are in the era of more expensive and higher-levels of sport at younger and younger ages, in virtually all popular sports. Without substantial economic support from home, a young football player has about as much chance at the NFL as a young rider has at riding at Intermediate eventing or above. Talent alone has no shot, any more than it does in horse sport.
In addition to the additional special equipment, private coaching, football camps, medical support for game recovery and injuries, the family must live where the young player will attend a high school with a top program that regularly goes to the playoffs for the state championship, which are usually affluent communities (average income $100k+). Etc. If the player is ever eligible for the draft or free agency, there is a whole other regime of coaching, practice, attending combines, etc., all on their own dime. No knowing if they will get a contract or even a chance at an NFL practice team.
New-entry NFL players may not have to come from millionaire families, but it is interesting how many do. As well as well-above-average income families. Of those few who manage to make it from families that originated from more modest circumstances, it is interesting how many have a close relative who is in professional sports and has the means to provide more help. It takes money as well as talent to have even a chance at the NFL.