I'm still thinking capitalism used to be best during the Cold War, when there was a competing system in the eastern bloc - this led capitalist countries to try to prove that they can increase the standard of living for all, even the less better off. Since that alternative turned out not to be long-lived, capitalism has been growing more and more ruthless...
This is I think the root of the problem. Capitalism (perhaps unsurprisingly?) works best when it actually has to compete with another world view. It would be nice if there was a competing world view that didn't result in hundreds of millions of deaths over a handful of decades, though.
I don't think that there even needs to be competition (although that works best) - you can make do with two other things: motivated citizens, and a non-corrupt government.
Laissez-faire capitalism doesn't work - that's pretty much obvious to everyone, and most people then take the next mental step of realizing that things sufficiently close to laissez-faire capitalism don't work, either.
The next realization is then "well, how do you stop yourself from sliding into something "sufficiently close"?" and the easiest answer is through carefully-controlled government regulation motivated by an active populace and a non-corrupt government.
Communism advocates, as can be seen in this thread, strategically ignore the fact that the same reasons that we're seeing capitalism "failing" (as this failure is incomparably better than anything seen in communist countries like the USSR and China), which are apathetic citizens and a corrupt government, are necessary preconditions for a socialist/communist model to even have a chance at succeeding - because, of course, they are either shockingly ignorant of history, or they think that they'll be the ones to come out on top and be the leaders of the new authoritarian government.
An under-examined problem is that one of the most successful products of capitalism is capitalists. Those selected for 'leadership' by the market are rarely going to be vulnerable to long-termism and empathy, or more generously are going to be the best at rationalising their own self interest (see Effective Altruists).
