And we have to remember, Quick was a surprise. He wasn't supposed to be the guy. You have to get lucky to be great sometimes.
The only missed opportunity after 17-18 is trading Doughty. However, other than him wanting out, I don't think he was going anywhere, even if the 17-18 team finished last overall. He's part of the Quick/Brown/Kopitar group. They all got their contracts, and if he wanted to stay, he was going to get paid for the Cups. It's not smart, it's not right, but it was something that was inevitable if he wanted it. Even if the Kings had a universally accepted great GM, I don't think he would've wanted to be the guy known as the guy that traded Doughty. Players like that don't move unless they request it.
Good or bad, I don't think that one can be put into the missed opportunity category.
Why do you think management has to placate anything? They've told us, repeatedly, that they are not about winning right now. That they fully expect this team to be bad for a while. That they cannot compete with the veterans on this roster. If Kovalchuk gets scratched, that's all a head coach thing. No hardcore fan cares. No casual fan is going to care or know what a Kovalchuk is. Management stopped trying to sell things a year ago. They're not trying to fool anyone anymore. They're trying to suck. Or, they've accepted that the roster sucks. They're done trying to pull a fast one on everybody. They're promoting college games because they don't care about the current roster.
He can quit, the cap hit just doesn't go away. That's why nobody is trading for him until at least the summer, and he's all in on playing the 20-21 season. Because nobody wants to be stuck with even 50% of his hit if it's dead space. Even then, Kovalchuk is a high maintenance player. You have to git him into a system, he has to find the right C to play with, he does his own thing, etc. Which means it's probably more likely that it's no earlier than the 2021 deadline before he's gone. Unless he goes back to Russia this summer.