I question whether the NFL is really worried about their players.
Drugs/roids in the NFL make for a faster, harder-hitting, more-intense product that has staying power for 4 quarters/16 games+. If you take the PEDs out of the equations, it is my belief, that the game would slow-down/be less intense. It wouldn't be as dramatic as switching from NBA to WNBA but game-to-game, week-to-week, season-to-season the "product" wouldn't be as "good".
Same goes for cycling, NBA, MLB. Doped cyclists make the Tour exciting by attacking the mountains; these are synthetic performances but they make for captivating television. Take out the PEDs and we're back to regular "human" performances. You or I might not mind that; and instead focus on the mano-a-mano competition with all its flaws and failures. For better or worse, we're living in a "doped society" (sports, study-aids, cosmetic surgery, etc) where anything less than super-human is inadequate - track/NFL are just closer to being honest about it.