Edited Jul. 23, 2021 at 10:15 a.m.
I'm going to play devil's advocate here: The last two goalies that signed a contract after one stellar season/playoffs were Jordan Binnington and Thatcher Demko. Both of them slipped to league average save percentage the following season. In arbitration, those would be the obvious comparables: similar age, similar experience (in the NHL anyways) and one good season. Binnington got a 6x6, Demko got a 5x5, and the arbitration might have landed in that range, should Ned's camp have gone into arbitration.
Nedeljkovic had never put up numbers like he got last year (.932, 1.90) at any level with more than a 6 game sample size. The last 3 years in the AHL: .903, .916, .906. A .932 this year in the NHL could either be an aberration, or a product of his defence (Mrazek had a very good save percentage as well this year, albeit with only 12 regular season games) . It could also be a massive natural improvement from a 25 year old goalie, but it's very likely that this does not last, especially in Detroit.
The last time Carolina went big(-ish) on a goaltender was Scott Darling, who immediately flopped after signing his 4x4.15 contract, and they may be skittish when it comes to signing a goaltender for that, whether now or in 2023-24, when Ned would hit UFA
Nedeljkovic immediately signed in Detroit for less than what he was reportedly asking for in Carolina, meaning that he was immediately willing to take a discount in Detroit, likely because he has family from that area. There is a chance that he simply did not want to re-sign with the Hurricanes and was willing to hold out (at least to arbitration which is never a good sign) to get a trade to either Columbus or Detroit. This may also be the reason that no teams were offering more than this in a trade, because he may have indicated that he was only going to sign in a city close to his family.
That being said, I still voted for Detroit because they obviously won this trade.