A sizeable number of Russians don't recognise Ukraine as anything other than part of Russia, as it had been for hundreds of years, for them Ukraine is just a difficult Russian province that broke away with the support of western imperialists, when Mother Russia was temporarily weakened by the fall of the Soviet Union.
Morality concerns the distinction between right and wrong or good and bad behaviour. So Putin could, at a stretch, ask "what could be more right for a Russian patriot than to make Mother Russia whole again?" But it would be a very big stretch. For Ukrainian self determination to have currency in Russia, it would require Putin and others to recognise Ukraine as an independent sovereign nation, but for many Russians Ukraine is not a sovereign nation, it is simply part of Russia, history shows that, so self determination is a moot point, it is not applicable and consequently so is any question of right and wrong.
Self-determination denotes the legal right of people to decide their own destiny in the international order. Self-determination is a core principle of international law, arising from customary international law, but also recognised as a general principle of law, and enshrined in a number of international treaties.
So if the Russian majority in those parts of Ukraine presently occupied by Russian forces decided, in a free and fair vote, to join Russia are you okay with that? Or perhaps the fact that Russia first invaded and drew arbitrary lines to gerrymander such a majority would invalidate such a vote? But then Russia considers Ukraine's borders as entirely arbitrary anyway! So down the rabbit hole we go.
I'll tell you what self determination is, it's the ability to draw a line on a map, hold the territory within it, and the people inside the lines to freely call it their own, and you need, and this is most important, powerful allies at your back to support you, that's what the Ukrainians are fighting for. it's what Kurds want too, except they don't have the ability to draw those lines and no powerful friends to help them.
It's all very well talking about "legal rights of people", you have to be recognised as a distinct people first by countries with clout, that's why Pep did this....
A small step, but an important one that Catalan is recognised as an EU official language.
To create a nation state and to hold it together in the face of external and internal threats to its existence is no small feat, ask the Israelis. The ideal state is one of unified purpose, and if not then consent and at the very least compliance, but be under no illusion, a young state exists only if powerful external forces support its existence. Right now that support for Ukraine is under strain and we will see over the coming months just how strong that support is, and if Ukraine folds for lack of support it'll all be down to geopolitics. Right and wrong, questions of morality, they're all points of discussion, but there are no absolutes here.
PS: Perhaps you could start a thread about the moral position of the United States in September 1939, or August 1914.