A lot of things could happen that would allow Russia to avoid invading Ukraine. We're in the world where they all didn't happen.
Western word from Ukrainian example will be seen as worthless as well. Two-faced proclamations where publicly West says "Every country is free to choose!" and privately tells very same governments "Not anytime soon".You are right, we're living through the start of the great war of our time. We're still in the phase were "the west" throws money at the problem and hopes Russia comes to her senses and stops the war. No matter how this turns out, the geopolitical landscape will be very different. Russia will be surrounded by NATO in the west simply because it makes no sense anymore not to be in NATO with Russia as a neighbor. Russias word is worthless.
Chinese are taking notes for Taiwan - there will be "defensive" weapon supplies and little else.
It will be bitter pill to swallow for West that Russia will not turn into North Korea no matter how much West struggles.Russia will be a paria just like North Korea is now. And it's her own fault.