“and was transferred back to Ukraine in 1954”
From 1783 until 1954 it was never a possession of, nor administered from Kiev. After 1954 it was still run from Moscow and has continuously been home to the Russian fleet from 1783 until... now.
You need to read some history.
Lol I am quite aware of history and your timeline is very shallow there was a lot happening before your 1783 date and if you use that date as a starting point much of the worlds countries have could have territorial demands the same as Russia I notice you did not address my Alaska scenario. Should we give the southwest back to Mexico and then back to Spain and then back to the people Spain took it from and then those give it back to the ones they took it from…. The fact that a some point Russia/soviet union controlled Ukraine and that they need that port is not relevant. They also controlled Poland east Germany Latvia Estonia and Lithuania does Russia have a right to take them back. Much of the world including Europe and their current borders have changed relative to the dates you cherry picked. Fact, Ukraine at this point Is a recognized and sovereign country. The idea that Putin does not recognize this and wants it back for his”greater” Russia and lebensraum, population and resources is irrelevant