The Russians learned more of history though. The Crimean war that happened long time ago was because someone took control of the sea. Who ever controls the sea controls all that surrounds it.
Ukraine was already lucky to have shared it with the rest but when they wanted to get enlisted with NATO, its a different path. NATO controling that sea will be the disaster of all countries surrounding there.
NATO lost its meaning, they even get Asian countries to join and also wants the middle east countries to join. North? They don't even build nations unlike the BRICS that helped making infrastructures so its no surprise that more countries prefer to join even the countries right in the backyard of US and EU.
This is only understood by people from oppressed countries though. Especially countrids that were bombed in the middle east when they say regime change but then leave the country in rubles. Countries like Iraq or Libya that was once properous but after the regme change, leave making the people worse. Stories people written online are written by people who werent there.
The Black Sea is a closed water area, where you can get only from the Dnieper, or through the Bosphorus, which is controlled by Turkey, which, in turn, does not want to see new Russian floating troughs in the sea, part of which belongs to Turkey.
And most importantly - remember, and never again fall for propaganda - until 2014, Ukraine had NO plans to join NATO. There were plans and projects for the modernization of obsolete Soviet junk, or rather, the abandonment of it, and the transition to new progressive standards, which it is logical to assume were developed and supported by NATO countries and not only. For example, India, purchasing weapons from the NATO bloc, did not become a member of NATO.
Well, listen to Russian propaganda - in 2014 they unleashed a war against Ukraine, solely because of the "Revolution of Dignity", which resulted in the flight of the pro-Russian President Yanukovych. And for Russia and Putin personally, this became a nightmare - an example of the overthrow of tyrant rulers, traitor rulers, and idiot rulers could come to Russia.
And the fairy tale about the fact that "Ukraine is joining NATO" was invented much later and spread through the pro-Russian media.