Not really. The Soviets had great scientists.
The Soviets did not go to the moon because their chief-scientist responsible for the Russians' journey to the moon died.
The first satellite was the Sputnik of the USSR.
The first man that went to space was Yuri Gagarin of the USSR.
The biggest atomic bomb on the planet was the Tsar bomb of the USSR.
The first efficient supersonic fighter was from the USSR. At the beginning of cold war the Russians knocked over 9 American fighters for 1 Soviet.
The first space station was from the USSR.
Who overthrew the Berlin Wall was the USSR (Mikhail Gorbachev).
What overthrew the USSR was its own economy. The Karl Marx's solution is utopian.
For this reason, Gorbachev implemented Perestroika and Glasnost.

You could claim the loser in every war defeated themselves.