I’m not sure if this is what you mean, but having preconditions of the sort involving pre-banning nations from applying to join NATO would cede too much to Russia. It would be a denial of something so fundamental to western society, the right to choose associations, which Russia agreed to in the Helsinki Accords, that it would represent a total moral capitulation.
Putin is many things, as you said earlier, like Berezovsky too, he is part street-thug. He does outrageous things, waits, and when he doesn’t get a response, he does something more outrageous. He had naturalised British citizens murdered on British soil, to virtually no response. Georgia, barely a whimper. Annexes Crimea, nothing. He has no reason to stop. A total military defeat and humiliation is the only thing that would stop the current conflict from dragging on and on, so it would be better for Ukraine if the West were to give Ukraine the tools it needs to finish the job. Safer, although worse for Ukrainians, would be for the war to drag out indefinitely into the sort of entrenched and pointless conflict Russia got itself into in Afghanistan. That way, the push against Putin would come from within Russia, whereas a total humiliation on the battlefield might actually help him consolidate power. If there’s one thing that can unite Russians, it’s the victim narrative.
I wasn't really talking about pre-banning any nations from joining NATO, although I think the original basis for forming NATO in the first place is no longer relevant in today's world. There seems to a dispute between those who believe that NATO's expansion is justified because Russia is hostile, while others counter that Russia became hostile precisely because NATO chose to expand. It's like a chicken-egg type question.
Obviously, every sovereign nation in the world has a right to free associations. But when you say "moral capitulation," the implication is that there is some moral obligation for other nations to intervene in another nation's conflicts. That, too, has been a sticky question for quite some time. As much as we would like the world to be moral, it really isn't, which is where concepts such as "realpolitik" come into play. It's a more realistic and pragmatic way of looking at things where we might have to choose among the lesser among many evils.
Putin is a thug, although compared to many of the other thugs the world has had to contend with, Putin seems more of a low-grade menace. Their poor performance of his troops in Ukraine would clearly demonstrate that the West really doesn't have that much to worry about in terms of Russian expansionism or any supposed plans to reconstitute the Soviet Union. But the bigger problem is driving them into the arms of China.
Another potential issue is that the US is also teetering on the edge of an abyss, politically speaking. I don't know how that's going to turn out, but considering your point regarding the right to free associations, the U.S. has that right as well. What if Trump gets elected and he pulls the U.S. out of NATO? What if he decides to ally himself with China and Russia? Would the remaining countries of NATO just take that lying down? Wouldn't they try to do something? (For the record, I don't think Trump would do that, and I don't even think he will be elected.)
But even setting aside Trump, I think people will have to get used to the idea that America is not a "white European" nation anymore. Not that it ever was, not officially, but we somehow always seemed to fancy ourselves as some kind of "Europe, Jr." (George Carlin reference.) Our Presidents in the future will look more and more like Kamala Harris and AOC, and not so much like Millard Fillmore. We also will have to accept the idea that this is a dual, bilingual society, with a large Spanish-speaking population with cultural and familial ties with Latin America. I would suggest that this will have the effect of slowly shifting America's geopolitical perceptions towards a more Latin American focus, as opposed to the Euro-centric view we currently hold. This could actually be a good thing in the long, for both the Americas and Europe.