As long as Ukraine refuses, Russia doesn't have carte blanche to arbitrarily rewrite the borders of former Soviet republics to suit its own domestic requirements.
Ironically, the party most benefiting from Ukraine's dogged refusal to give up its right to tell Russia to pound sand is Belarus.
Glasnost, followed by the 1998 devolution of powers to the local soviets, established the principle that Russia was the center of a Union comprised of states that have self-government. Each republic was empowered to explore its own identity. That principle was further enshrined in the CIS Charter.
If Russia can annexe regions of other nations militarily - and do so legally, and against the wishes of those other nations - then that rips up a 34 year old principle established by Russia first, fed thru the Supreme Soviet, and cascaded down to local Soviets.
Lukashenko, and several other leaders of what used to be local Soviet republics, should be concerned - it's only because of that principle that they have real power over their own countries.
Many Muscovite nationalists want to reverse that entire process of devolution - claw the regional power structures back into Moscow, and rule from the center. To them, all UN Charter recognition, and all independent statehood, is illusory. They don't recognise the Baltics, Belarus, Ukraine, or the 'Stans as properly independent - their attitude is, ALL OF YOU BELONG TO MOTHER RUSSIA.
On Saturday, a guest on Rossiya 1 insisted that Belarus is part of Russia. To the utter horror of Vadim Gigin, who amongst other things is Chairman of the Belarusian Society Knowledge Association .
Even after the correction from Gigin that Belarus is actually an independent republic (i.e. not a district of Russia!), the other guy retorts, "Belarus is Russia".
Today, Lukashenko said: “As far as our participation in the special military operation in Ukraine is concerned, we are participating in it. We don't hide it. But we don't kill anyone. We don't send our military personnel anywhere. We don't violate our commitments.”
It's very difficult to not see that as a warning shot to Moscow: Belarus is the closest it still has (with the possible exception of Chechnya) to a loyal lapdog but even it has its limits. It has signed multiple agreements of non-aggression and recognition with Ukraine AND THE OTHER SSRs, and it regards the principle of self-determination behind it to be sacrosanct. It will not launch an invasion on Ukraine, no matter what Moscow tells it to do. And, if the Muscovite ultranationalists insist on treating Belarus as if it were simply another district that needs to take orders, it might just find that Belarus stops cooperating.