I'm excited that they signed Samsonov, too, but I'm not ruling out the chance he plays a year in Hershey to learn the language, the culture, and the narrow rink.
I get totally annoyed when fans of other teams post builds where they trade the Caps someone expensive and not as good as Carlson, and then sign Carlson with the cap space they created, so I assume Isles fans are just too polite to tell you what they're thinking.
https://novacapsfans.com/2018/05/04/capitals-sign-goaltender-ilya-samsonov-to-three-year-entry-level-contract/
Yes, the team above is good, but teams rarely trade NHL ready #1 picks they've signed and developed and are all set to debut. Like, the Caps did that to get Jagr after he led the league in scoring.
You could certianly get two first round picks or Parayko for Kuznetsov, but not likely two developed, signed, ready for prime time recent first round picks plus Parayko for just Kuznetsov.
Is Kuznetsov better than all of them. Yes. He's about as good as Tavares, and cheaper, so just keep him and sign Tavares and Carlson, like every other team would like to, if they both want to come play with Ovechkin and win a Cup together. Or try the harder puzzle of building a long term winner without most of the answer being deus ex machina.