Russian President Vladimir Putin will go down in history as having lost Ukraine for good. Putin has experienced two geopolitical tragedies with the disintegration of the USSR in 1991 and disintegration of the Russian world in 2018.
Before todays move, the Ukrainian Orthodox Church which came under the Moscow Patriarchate accounted for a third of its total parishes and their loss reduces the size of the Russian Orthodox Church to that of the Romanian Orthodox Church. Within Ukraine, the Russian Orthodox Church will become a minority church with its influence severely curtailed. In the political domain, its main supportersParty of Regions and Communist Partybelong to pre-2014 Ukrainian history while its current allies, the Opposition Bloc, are bitterly divided and weak.
Autocephaly adds to the deterioration of Russian soft power in other areas. On December 20, 240 parliamentary deputies voted to require the Ukrainian Orthodox Church (the official name of the Russian Orthodox Church in Ukraine) to re-register as a Ukrainian branch of the Russian Orthodox Church. As most of their parishes are in western and central Ukraine, a large number of patriotic Ukrainians will desert it because it will be henceforth openly linked to Russia. Two-thirds of Ukrainians view Russia as an aggressor country.
https://www.atlanticcouncil.org/blogs/ukrainealert/how-putin-lost-ukraine-for-good
Background
Ukraine Orthodox Church granted independence from Russian Church
https://www.bbc.com/news/world-europe-46768270