What would alternative be? Worker run cooperatives have not been particularly successful so far. Serf had no choice of "changing a job" but a modern worker presumably has a lot more freedom to choose their employer.
The basis of capitalism is competition. The theory depends on no single company having the power to move the whole market, but this theory is getting decimated by the empirical reality of consolidation and monopolization.
We all forget, because 9/11 happened literally a few days after it was announced, but the new Bush administration decided to give a wrist slap to Microsoft instead of breaking it up, which was the proposal of the Clinton administration. That's essentially when antitrust laws ceased to exist, and in the wake of the failure to do anything about Microsoft, mega-corporations and monopolies have thrived.
The basis for why this is at all acceptable as a system to organize society is that competition, government restrictions, etc, whittle down private power to somewhat tolerable levels. There must surely be a better system which we haven't thought of yet though.
Many people, especially Americans seem to confuse capitalism with 'trade', 'competition', 'markets', etc, whereas I mean it as the private ownership of production, the profit from other people's work, etc. That seems fundamentally immoral in some ways from the very start.
Eg, I read an article about working with Elon Musk recently (https://www.businessinsider.com/working-for-elon-musk-spacex...), where they said "If there are employees not aligned with that vision, he will chew them out and he will do it in a vicious way, which is his right as owner.". I mean, no, we really should not be enshrining that, or even really tolerating it, in a decent society.
The question then is how should we allocate resources (capital), how should we incentivize risk, innovation, hard work, etc, What kinds of ownership are moral, etc.
I suspect we'll be stuck with some form of capitalism for a while though - like democracy, it's the worst system, except for all the others, for now.
Common != Successful.
The fact we don't have many Mondragons probably has less to do with its intrinsic efficiency and more to do with pre existing wealth distributions.
>What would alternative be?
One change that Jeremy Corbyn put in his manifesto in 2017 was a law mandating one worker board seat for companies over a certain size.
I didnt think it was a particularly drastic change but it drove the big business lobbies into a fit of white hot rage.