You could ask the same about “free market” capitalism, it’s impossible to have a successful truely capitalists economy too, the US is a mixed economy, China is also a mixed economy… Any future “socialist” based country would still have a mixed economy… The issue is not socialism vs capitalism, it’s a question of how much regulation is needed for the economy in order to minimize the suffering of people overall while increasing the average quality of life.

Some things are better handled collectively and with strong regulations; you probably want your heart surgeon to have a medical license, but you also probably don’t want to have to give up your house and life savings to get said surgery, you probably don’t want the plastic manufacturing company up river from your drinking water to just do what’s economically most profitably and dump their waste into the water, but you probably don’t want to pay the price for bottled water to nestle every time you turn on the tap either.

Since you’re on a reading kick maybe look into some of the past attempted creations of liberatian “utopias” and ask youself why anyone would be foolish enough to think that model might work,

I’d suggest to start: A libertarian walks into a bear.