The NBA doesn’t have a hard cap either. They have the same ridiculous soft cap the MLB has, the Cavs right now are nearly 50% over the cap.
The tax doesn’t serve as a disincentive to hoarding. If it did the Yankees wouldn’t have turned themselves into a collection of antiques. Hoarding is still clearly going on, The Nats have such a hoard people keep insisting they’ll be the best team ever. The Dodgers are a hoard, the Red Sox. And right now the Cubs are trying to become a hoard. Of course the punchline is that’s not actually a good way to build a team, especially not in a sport with guaranteed contracts, your hoard becomes you prison as you suddenly find yourself with half your roster being 3 years past their prime with 4 more years on their contracts.
Never believe what a team says about themselves. If teams spoke the truth about themselves the Cowboys would have won half a dozen Superbowls in the last 20 years instead of 2 playoff games because they’d have actually been the team Jerry says they are. The math for the Yankees has been obvious for a while, too may players that are too old with too many years left in their contracts. It became even worse for them when the league finally started testing for ‘roids and a bunch of the older players in the league suddenly started acting their age. The Yankees got obsessed with holding onto the stars that gave them a bunch of pennants and started thinking they were just one or two more good players from getting back, that’s when teams start making free agency splashes, that’s when teams start over paying, that’s when teams start signing has beens, to long term guaranteed contracts, and they wind up in the situation the Yankees are in. The problem for the Yankees isn’t that they’re way over the cap, the problem is they’re way over the cap AND stink. If they were winning their division and going deep in the playoffs like they were in from the 90s through 00s they wouldn’t be dumping cap now, they’d be ADDING so they could keep it going.
The NBA doesn’t have a hard cap. The only hard caps in America are the NFL and NHL. If you violate the caps in those leagues you lose draft picks, no BS with a luxury tax, you get actually punished.
The NBA has a hard cap, but with a major exemption, as I noted before. (You can not exceed the cap for free agents, but you can to re-sign your own players. So if the Knicks wanted to get Stephen Curry from the Warriors, they’d have to fit him within the cap — but if they re-sign Carmelo when his contract is up, they can go pretty much as high as they like.)
Teams manipulate that all the time.
There are actual penalties in MLB for going over the threshold. They’re monetary penalties. Only a few clubs are currently paying them. It does serve as a disincentive.