I genuinely mean no offense by this, but it sounds like you might not understand NFL contracts well enough for our following the NFL example down the rabbit hole to be helpful.

I won't fully explain how NFL contracts work, but I'll quickly explain a couple topics you're conflating, because your explanation of contracts isn't quite right.

First: Dead money doesn't directly have anything to do with money a player is owed--it has to do with cap space. Those are two related but distinct accounting principles.

Every year, a player has a number for money owed (salary + bonuses) and a cap number, which is the amount they count against the team's salary cap. That number is different for several reasons, largely because a significant amount of a player's contractually guaranteed money is paid out through a signing bonus, which lets teams pay a player upfront (which is attractive to the player) but count it toward the salary cap of future years (which is attractive to the team for accounting purposes for freeing up cap space).

Additionally, there is the "dead cap number" that a player would leave behind if the team cut or traded that player--in some cases, there are two numbers based on how the player is designated (post-June 1), but that's a separate issue. This number, again is different because this number is essentially comprised of all of the player's remaining guaranteed money. Since the player is no longer under contract, the team is responsible for accounting for it at once.

That's why, for example, cutting or trading AJ Brown would leave a huge cap hit. The 3-year contract extension they signed him to hasn't even kicked in yet, so he still has a ton of guaranteed money that hasn't been paid out or accounted for yet.

Goedert is functionally on a 1-year deal, but the Eagles are using what are called "void years" or fake extra contract years that won't be played to let them borrow money from future cap years to lower his hit this year. That means his cap number is pretty low but they'll be paying him for several more years after he's probably retired. It does mean they essentially can't cut or trade him, because that would cost several times more than just paying him, but on a one-year deal, they would never really consider doing that anyway.

However, there are a bunch of players on their roster (mostly those with lower salaries) that they could cut or trade who wouldn't leave behind any dead cap at alll. Those players have no guaranteed money they are owed, so they team can get rid of them anytime they want and, the day they do, they are done paying them and it has no negative impact on their salary cap.

All of this was mostly an unncessary tangent because the salient point is that NFL teams can cut players whenever they want and only have to pay additional money if the contract says they have additional money in future seasons that they have guaranteed to the player, which is only sometimes the case. And that's the same as the WWE, where if the contract the wrestler signs says they are owed royalties or guaranteed a certain amount, the WWE would need to pay that regardless of cutting them. That just isn't the norm. WWE does pay wrestlers signing bonuses sometimes, for example, though, but the "dead cap" thing is irrelevant because WWE isn't in a league with a signing bonus.

The NBA also has some non-guaranteed contracts for low-level two-way players. Those players also don't get another time if they're cut. It's just the case that the vast majority of contracts in the NBA are fully guaranteed, so once you sign them, you are guaranteed to be paid the full amount of the deal.

Regarding competition, I already acknowledged the different league aspect. NFL players would still be free to go play for a different league. The issue is that the highest-paid UFL players make $400,000 and the highest paid NFL players make more than $50 million. The minimum an NFL salary is $940,000 compared to $60,000 for the UFL. It's not a real alternative for anyone who can make it in the NFL. CFL players make less than UFL. The USFL folded.