What would need to happen for a salary cap to come into place:
1) Owners would need to open up the books (never happen)
2) Wealthy teams would have to share more revenue (never happen)
3) Players would have to be ensured a percentage of total team revenue (ticket sales + tv) every season (this is how it works in every other sport - MLB Owners would never agree to it)
4) Arbitration/player control would have to be massively reworked