You said Soviet Union badly needed reform than said that reform caused the whole thing to fall down. Pre-reform Soviet Union was doing fine by most measures, soviets under Brezhnev had slow but steadily growth in every sector. Reforms ruined everything that's why Soviet Union fell, if you think Soviet Union fell because it couldn't provide to its citizens you would be wrong since post soviets states were MUCH worse and they didn't fall. Soviet Union could have survived if it wasn't for Gorbachev's dumb reforms.
No, that's not how reforms work, there's no one type of reform and there isn't one approach to reform either, Gorbachev's issue was two fold. Firstly, he tried to reform too much at once by introducing both Perestroika (restructuring) and Glasnost (opening)
at the same time, this was a big mistake. Contrast this to the PRC under Deng, whose reforms were more gradualist. Secondly, Gorbachev did all this while trying to save socialism when he should have taken the USSR on another road and introduce real market reforms to re-invigorate the ailing Soviet economy. Again using China as an example, the party leadership decided to adopt a pragmatic approach and change course by introducing a market economy.
What I'm trying to say is that while the USSR needed reforms the leadership of the CPSU were clueless as to what type of reforms and how to adopt it. The economy under Brezhnev was basically a petro-state and high oil prices in the 1970 gave them a false sense of stability.