You're telling me when the cap system was put in place, the NHL and NHLPA wanted a situation where one team (Arizona) is getting to the cap floor by taking on LTIR contracts while another team (Vegas) actively manages when players come back from legit injuries so they can go over the cap in the playoffs?
I'm going to split this into two parts:
1. Arizona - I think there was a > 30% chance someone thought of it, but no one was too bothered by it. Alternatively, I think people recognized there may be situations where a team may need to be at or near the cap floor for whatever reasons, and if it happened via LTIR, OK. That said, I know there's been years where Arizona is actually capped out due to contracts that would be on LTIR elsewhere, and then has to use LTIR on one or more of those contracts ... but, its cash layout is at the cap floor - which, since 2012 there's a requirement for teams to have total salaries that reach the cap floor, and Arizona's LTIR contracts are contributing a little but not like tens of millions of dollars to it.
2. Vegas - I'd say there's a 99.999999999% chance no one thought about this. The other 0.000000001%, someone did and no one was bothered enough about to say "you know what, maybe we need to think about this more and figure out a solution for it."
Fact that the Lightning actually complained about it tells you that's not what was intended. You could claim its an unintended consequence of how the rules have been set up and they're just leaving it as is, but this is not what was intended.
There's been
a lot of unintended consequences from "fixes" to "problems" and everyone just rolls on with it anyway.
Limits on contract lengths to fix ultra-long contracts? The problem was never guys at 24 getting 9-year contracts, or guys at 22 getting 11-year contracts. It was guys getting 11-year, 12-year, 13-year contracts and/or contracts that took guys out to 43 and were ultra-front loaded with the clear intent of circumventing the cap by having the player retire - or, "retire" - before the end of the contract. And, never making their signing teams pay back all the cap savings they realized in the years they had that player under contract, playing for them.
The "solution" was declaring all contracts over 7 years as "bad" [over 8 if you were signing with the team that held your rights] and artificially restricting contracts lengths accordingly.
Matthews signing for 10 years at 21? You probably expect him to still be playing at 33.
McDavid signing for 12 years at 21? You probably expect him to still be playing at 33.
Marchessault signing for 8 years at age 33? You probably
don't expect him to still be playing at 41.
The first two contracts? Those are null and void, they're prohibited because they're
bad. The third? Oh, that's still perfectly legal - and, it can still be structured in a way to circumvent the cap [albeit not as blatantly as before]. And, Matthews and McDavid now carry significantly higher cap hits and thus reduce cap space for their respective teams than if they could have signed for a couple more years at lower salaries that would have brought their cap hits down. And, that reduction in cap space makes it more difficult for teams to keep other players - which has caused people to propose "solutions" to that "problem" that create other problems they never think about, because they're only focused on the "solution" they want to put in place.
Oh, and teams
still don't have to pay back cap savings they realize - which then allows teams like Arizona to have to pay it back instead and thus reach the cap floor, which pisses people off.
But, we put in uniform limits on contract lengths and "solved" the "problem" of teams signing ultra-long contracts that might circumvent the cap. Hooray, everyone.