Can you please add some proofs for all your statements?
As a person who been living in Crimea for big part of my live I do find your comment very disconnected from reality.
From strategist perspective Crimea does not have anything to give to Russia except logistics problems and few military bases.
Ukraine has way more claims for Crimea rather than Russia. If we gonna use your logic than Russia should give back to Ukraine Kuban oblast (which for long time were part of the USSR)
Crimea had its own parliament but saying it was independent its an open lie. Crimea belong to crimean tatars. Which been deported from Crimea during Stalin genocide. But if we go with your logic, crimean tatars should be the one who are the real "owners" of the Crimea, and they are pro-Ukrainane. Simply cause russia to this day killing and torturing them.
Nothing with Crimea occupation is unique. Dictatorship government occupy new territory, silencing and do genocide so then it will be easy to fake referendums.