This is a tough one. The Soviets (who indeed helped to start the war) lost 10s of millions during the war. The Germans fought them tooth and nail up until the last day of the war. Lots of Soviet soldiers died in what is now free eastern Europe. Of course they put up monuments to their dead in ‘The Great Patriotic War’.
And of course, the people of east Europe soon realized that the Soviets were invaders and occupiers of their nations. They had virtually no say in the.matter. When they got their independence with the fall of the Soviet Union, they viewed the monuments as eyesores and painful reminders of Soviet conquest.
The Soviet soldiers’ graves should remain sacred ground. The monuments in the middle of town should be removed but not destroyed even though the pain they may give is so much fresher than any statue honoring Confederate soldiers.
The Soviets lost 10s of millions yes, fighting their erstwhile ally.
The Soviets did not “free Central or Eastern Europe” — unlike the British and American forces. Instead the Soviets conquered central and eastern Europe.
It was replacing one totalitarian regime with another
“...they viewed the monuments as eyesores and painful reminders of Soviet conquest...”
Note the difference - when the US troops fought Nazi Germany in WWII they liberated Europe and they returned home, not only leaving those countries to govern themselves but helped them re-build. Those people still love the American GI.
The countries liberated by the USSR remained under USSR dominance with both USSR government and military in place. Those eastern European countries hate the occupiers.