Like all simple economic theories, it looked good on paper, and convincing to the crowd. Then it turned out that the new owners were largely the same people who were in charge in Soviet days, except for a few talented and lucky grifters who made their way from the very bottom to the very top.
(Side note: Zelensky's "Servant of the People" is available on Netflix with decent subtitles, and I would heartily recommend it to anyone in the West who wants to understand the historical trajectory of former Soviet republics - Russia and Belarus especially, of course. What I found interesting is that, while it was targeted at contemporary Ukrainians in 2015-2019, the world that it depicts was very familiar to me from my memories of 1990s in Russia, aside from uniquely local issues like the languages.)
The difference is that one of Russian oligarchs decided to make a new political puppet with a "strong man" image. He was very successful, but then the puppet decided that it can make it on its own - and did so.
A big part of it is that the "democrats" (which was a catch-all term for all Western-minded liberals) favored a quick reset of the vestigial planned economy into a free market-based one; words like "shock therapy" were thrown around. The idea was that any inconveniences would be temporary, and more than made up for when the transition is complete.
The immediate result, however, was a significant drop in quality of life for the majority of the population, with a corresponding rise in crime. And because the "democrats" were the ones spearheading the efforts, they carried the reputational hit. This gave people like Putin the opportunity to ride to power on "strong hand" policies that were supposed to fix all that.
I grew up in Russia during that era, and remember the rhetoric then. One thing I'd say the West did very wrong was to let organizations like the IMF run wild, pushing for their (austerity-centric) ideological view of the economy through loans. Then again, from what I've read later, it wouldn't be the first or the last time they messed up a country they were supposed to help.