I am genuinely interested how such a thing would be done. I understand that it wouldn’t be as hard as with communism, but I can’t think of any way to encourage companies to make better (genuinely better) products. I remember how my mother told me how in her days (she lived in the DDR) there wasn’t really any reason to be better than another company, as they would all be payed equally.
Look at video game modding as an example. People want to make better things. It’s part of our nature. Even today, where they have to devote their free time to it and still work under our exploitative system for money, we have people devoting time equivalent or in some cases even greater than a full time job in order to make amazing high quality mods with no monetary reward for doing so.
If the system supported it, we would see that kind of behavior in all sorts of fields.