The gains from capitalism have dropped the costs to produce foods to previously unheard of levels. The productivity of a modern farm is incredible compared to farms of 25, 50, 100 years ago. The amount of labor and land needed to produce the food humanity needs has dropped considerably.
I realize these are not the statements that people posting here want to read, but that's reality. Take the good with the bad because regular capitalism is not bad. Unfettered capitalism is the problem.
But that's not because of capitalism, that's because of technological advances. We have centuries of technological advances in agriculture before we even had proto capitalism. There's no reason to believe those advances wouldn't have happened under any other economic system.
Capitalism is exceptionally good at short term efficiency, because it's profits driven and and as long there's someone else to compete for profits there's technological advancement. But capitalism is also all consuming and once it's killed off all its competitors and profits are guaranteed the efficiency of technological advancements stops. Xerox is a great example, they invented a lot of modern things we use today like the foundation of the personal computer, GUI, computer mouse and desktop computing. But they invented those things at the height of their success and because of it did almost nothing with it. They just didn't need to because they were already making loads of money. Those ideas were instead taken by Microsoft and Apple and they found immense success in it. Had Xerox also killed all the competition then the world we know today wouldn't exist because there wouldn't be any need for tech to advance here. The efficiency capitalism gives comes from a purely external source, it's to beat the competition for profits. Once competition dies out so does the efficiency. Long term capitalism is not more efficient than any other economic system where the efficiency is derived from an internal source, such as the desire to do less work.
And while we're on the topic of efficiency, the efficiency of capitalism is not necessarily a good thing. Do you know what is efficient? Working from the moment you wake up until the moment you have to sleep. That is what capitalism, at its core, wants. But I doubt it's something you want. In fact we collectively have decided it's not what we want because we have laws that exist solely to limit capitalism. The fact that you have time to comment here is inherently anti-capitalist, because capitalism wants that time spent on making a profit.
What you are describing in the later part of your post is essentially unfettered capitalism. Fuck everything about unfettered capitalism, but regular plain old capitalism is, as you said, great for tech innovation. Too many people can't keep the two straight.
You do realize that we have roughly 3-4 millenias of technological advancements, before we even invented early capitalist theory? The vast majority of human history contradicts your statement.