I'm not a fan of professional sports, particularly most team sports. The reason is that many of them are "freak" shows, in my view.
Yes, most NBA, NFL, NHL players are very good. Some are great, even. But the fact is that the NFL and the NHL are, largely, arms races for the largest players. The NBA is an arms race for the tallest players. So, important is weight and height in these leagues that skill often is of secondary importance.
Let me suggest some rule changes to improve these leagues, the game, and open them up to a larger pool of better players. Restrict the maximum weight of players on the field in a NFL game to 1,800 lbs. for an average player weight of about 160-165 lbs. The game would be much faster, and a larger pool of skilled players would emerge. If a team wants to field a William "The Refrigerator" Perry at 380 lbs make it a requirement to put smaller players on the field at the same to meet the rule. I can see it now "The Refrigerator and the Seven Dwarfs".
Let's do the same for the NBA. Add a rule that restricts the cumulative height of the players on the court at any one time to 28-29 feet for an average height of about 5' 8". Again speed and skill would increase.
If an NBA team wants to field a Gheorghe Muresan at 7' 10", the rest of team will likely have to be former jockeys.
Moreover, such changes would mean a much larger cohort of young people could participate competitively in these sports.
Weight restrictions are not new in sports. It happens in boxing, for example, and it happens in horse racing.
We know that in many sports height and weight afford advantage that cannot be compensated by other players' skills.