You overlook 1 major flaw in the Montreal trade (aside from Kuzy's off ice issues). Romanov is a LHD not a RHD and Montreal coaching has said they prefer to use him on his natural side. He often gets used on the right because Montreal is as thin at RHD as Washington is. Literally our only RHD in our entire organization are Petry, Weber (who both have maybe 5 years left at best) Brook, Fleury and Hendrickson (Hendrickson likely never makes the NHL). So out of 90 players organization wide we have 2 aging and 2 very young RHD. Yet you propose us to give up our best young RHD.
You overlook weeks of conversations, mostly among Habs fans, about what they would like to offer for Kuznetsov.
As another Caps fan following this conversation, this is not a Caps fan proposal. Just a quote of a MTL fan post, based on a comment they made in a conversation, as part of a series of MTL posts bargaining down after another MTL fan suggested Kotkaniemi and MTL's 2021 1st. Like it says in the description, Brady has been asking around and following posts about Caps players. Read this one back on the MTL side? It keeps coming up.
Here's one recent post that offers the above (WSH giving Kuznetsov and taking Byron, MTL giving Brook and a 1st) and throws in a 2nd to take Drouin: https://www.capfriendly.com/armchair-gm/team/2404379 Not sure if that's fair or not, but WSH would need to clear more cap space in another move to make it work, unless Seattle takes Drouin.
Here's a variation with a 1st, two 2nds, Norlinder, and Poehling for Kuznetsov and Jensen: https://www.capfriendly.com/armchair-gm/team/2402440 if MTL is adding a top center, that makes it harder for Poehling to make the team next year, so by your logic of keeping depth at all positions, and needing RD, maybe that's a better idea? WSH currently has one AHL RHD: Paul Ladue. He's 28 and his contract is expiring, but they called him up for playoff depth so I wouldn't be surprised if they bring him back.
Here's a Habs fan posting the above trade plus a MTL 4th: https://www.capfriendly.com/armchair-gm/team/2401469
A Habs fan offered Drouin and a 1st for Kuznetsov. There's an Oilers fan in the comments who thinks the Caps should take Drouin for Kuznetsov straight up, but it's not clear whether he is Peter Chiarelli or the last surviving anti-Peter-Chiarelli troll account: https://www.capfriendly.com/armchair-gm/team/2399681 Either way, the idea does not help the Caps' depth chart unless Drouin can play #2C and occasionally score 70 points a year there. It would still be a little light. Is there a center the Caps could get for Drouin, somewhere in the league? They have pretty good NHL wings. (as an aside, here's a Drouin to WSH trade that includes a center and takes away a wing from WSH, without taking away from WSH's weak center depth. Not sure it gets any interest unless MTL sweetens it even more, but it seems more realistic than Drouin for Kuznetsov: https://www.capfriendly.com/armchair-gm/team/2388223)
Here's a Devils fan reposting Kuznetsov for Kotkaniemi and a 1st. I said in the comments the Caps should keep Kuznetsov, but after another quick first round exit, I'm beginning to see the reasoning behind getting younger. https://www.capfriendly.com/armchair-gm/team/2383142
Here's a Habs fan posting Drouin Kotkaniemi and a 1st for Kuznetsov and Lapierre. https://www.capfriendly.com/armchair-gm/team/2382077 Another Habs fan commented that isn't enough for Kuznetsov alone, let alone to add Lapierre. I think it's enough for Kuznetsov, even though WSH does not need Drouin, and does need a #2C. They can try Kotkaniemi or Eller there, until McMichael or Lapierre is ready. Since the Caps have four solid top-four wings in
Here's the post that got the conversation started: Hawsie suggests Kuznetsov for Kotkaniemi and a 1st. https://www.capfriendly.com/armchair-gm/team/2379255 In my comment I offered to add Kempny. Obviously with Kempny coming off a full season of sitting out with injuries, it's debatable which side that helps. But the point is that even though WSH has no RD prospects, nobody is obsessing over how to pry Josh Brook away from the Canadiens. It's more of just a listening process, hearing what most Habs fans want to offer for Kuznetsov that could sort of help the Caps.
So, you know, yeah. MTL could totally keep Brook and add a #1C. If you want to keep the top-four RD prospect, you can certainly go back to offering the top six center prospect and the pick. It doesn't help WSH's depth charts quite as much, but the value is there. Or you can be opposed to adding a top playmaking center. Kuznetsov is a polarizing figure around the league, but his teammates speak well of him, and they didn't publicly speak well of Burakovsky or Vrana, so I would not be surprised to see Kuznetsov stay in Washington and just keep contending.
eta: that's not even getting into what CGY and CBJ fans are offering for Kuznetsov. I've seen Monahan and a 2nd, Domi and a 1st, and Foudy and a 1st. Or CGY's 11th overall pick, plus Kylington. WSH fans rejected the latter because, like MTL, too many LHD.