Everyone thinks so (for no good reason I can see), so nobody tries. This doesn't mean the idea itself is actually bad.
> Do we really need everyone in a company voting on product ideas/direction when many don't even know or care about it in the first place?
This is a valid concern even for democratic governments. I don't think it's contradictory to the idea of a democracy. There are ways of making this work better e.g. weighted votes based on some criteria; I'm not interested in armchair-theorising about it though, we need to try it out and gather data on what works and then form theories about why.
> It seems, from your other comments, that you don't want to risk your own money and start a company like this (where everyone has a say)..you would rather force existing companies to use this structure..which is ridiculous.
I don't have enough money to risk this way. If I did, I would. "Force" isn't feasible, and you're extrapolating me here, but perhaps the market can apply pressure, in the same way you might boycott an unethical company. (As I noted elsewhere, this is more feasible today because you do actually have ethical alternatives, as opposed to a few decades ago.)