Quoting: EatMyScoobySnack
Reinbacher is seen as a defensemen like Seider so I'm pretty sure there team who would select him over other player who was supposed to be higher drafted. And while moving back is sometimes good to acquire what you want and getting more asset back, you game the chance that another team would select the same prospect you wanted and you find yourself without what you have wanted.
I think Detroit played head games with everyone when they took Seider at 6 because Seider wasn't even supposed to be that good; he was all but unanimously agreed to be a top 4 prospect. Now there's another guy who's a unanimous top 4 guy (and I saw an interview, saw nothing really stand out about his character), and someone will grab him top 8 in the "legendary 2023 draft" it might be known as in the future... he could end up being a Noah Hanifin (though I don't think he'll be this good because Hanifin had unanimous top pair ceiling) when you pass on Timo Meier, Mikko Rantanen, Kyle Connor, Mathew Barzal, etc. If Michkov isn't available and Detroit offered me that package, I would take it, because I do think that if someone drafts Reinbacher, you get Dvorsky, Benson, or one of the two American guys who might well be better than Smith is.
Montreal trading down could be further gamesmanship... them saying "Oh we're drafting Reinbacher" but they're really not... and they end up getting an elite forward like Zach Benson at 9, whom they really wanted at 5, and then get a massive upgrade over their 2nd first rounder, and take another potentially elite forward or a D like Simashev if he drops down that far.