If NATO's response isn't "we do what we want, fuck off" they've lost the next war already.
I think the powers that be are the ones who are resisting intervening or even bearing their teeth ~ because in reality, they'd rather just go back to trading with or at least ignoring Russia.
So much so that they'd far sooner appear indecisive and capricious, avoid direct involvement, and have scope to return to the status quo (regardless of the blood being spilled) as quickly as possible, never mind what happens to Ukraine.
Well, at least if enough missiles and/or fighter jets are placed on its soil by NATO countries to effectively close the Baltic Sea in case of war.
Given how narrow Öresund is, I'm fairly sure conventional artillery (not to mention missiles...) could cover the entire strait from the coast of NATO member Denmark. I doubt Sweden would protest too loudly about this incursion on her territorial waters, if she lets the Russian navy do the same first... And even if she does, so what?