The democratic state itself has no real power since the politicians are owned by special interests, those special interests usually being large companies.
If is through the State that they exert power, it is the State system where the power lies. For everybody else, it is considered a crime if they steal, murder, rape and torture. But for State agents, it is considered not only acceptable, but a social good (or necessary evil). The State is the only agency that people at large will accept this from. They won't accept it directly from the companies. Hence the power lies with the State, not the companies that happen to control it temporarily. And as I explained, many countries in the past and present have had very large, powerful and destructive States with not a single large company in sight, and while these companies were made illegal just like you propose. The problem is not the companies. The problem is the delusion that gets the masses to accept oppression if it's coming from someone in an official uniform. Your proposal makes these people in funny costumes a lot more powerful. Your proposal is nothing but rebranded socialism. And I'm not even sure about the rebranded part.
No, it isn't the same thing at all! Attacking capitalism does not imply socialism at all, as there are multiple other anti-capitalistic, non-socialist philosophies such as individual anarchism, fascism and libertarianism.
Capitalism simply means economic freedom for everyone in an area. Socialism means economic slavery for everyone or most in that area. There is only one axis along which this can be measured. You're either for freedom, or you're a socialist. Sure there are points along the middle of the line, like fascism. Libertarianism and capitalism in this sense are one and the same. Your ideology, by your own explanations and suggestions, is much closer to socialism than even to fascism.
However, a meritocratic society based on peoples' real personal value/contribution to society rather than money, would be the best option.
That is what capitalism is.
Making them less productive is The Whole Point
Socialism is the only ideology which can claim that they want to reduce someone's productivity as a goal in and of itself. When someone is more productive in a civilized society based on trade, everybody in that society, -except their competitors-, benefits. The only reason to want to destroy that is out of envy. Socialists feel better when others are made worse off, even if they are made worse off too in the process, because it quenches their envious nature.