This is delusional. (It reads more like an apocalypse than a scholarly analysis of the real-world situation. https://en.wikipedia.org/wiki/Apocalypse )

Ukraine has now lost too many men to KIA to be able to mount an offensive that penetrates more than a few tens of kilometres. They will be lucky to penetrate even as far as they managed with the autumn offensives towards Kreminna and Kherson (the latter of which came at a huge cost in men KIA). They are hopelessly outgunned by the Russians.

The only way I can see Russia ever leaving Ukraine, is possibly after a decade or two of asymmetric warfare. In much the same way as the Taliban were able to finally defeat the USA (except that it will be in a steppe landscape that doesn't seem to lend itself to guerrilla warfare).