It seems that most workers prioritize a steady wage without the risk of being an owner. And it's difficult for worker cooperatives in capital-intensive industries to attract outside investors; investors who put in significant amounts of money quite rationally want some control over the enterprise rather than leaving the decisions up to workers.
One of the most prominent examples of employee ownership was with United Airlines. Employees gained majority ownership in 1994. That kind of worked for a while but ultimately failed, ironically partly due to labor union disputes. It seems the workers had trouble deciding how to share the fruits of their labor.
We've set up our society to make it difficult for worker owned businesses.
In short, worker-owned businesses are rare because individual workers are poor (relative to the capital that's needed) and they can't get external funding because the investors want control in return, which labor management can't provide.
That's why most large-scale worker-owned businesses are part of a federation supported by a bank - e.g. Mondragon's Caja Laboral. Institutional design indeed does matter.
Talk about founding a workers co-op that's democratically run? With shares issued to each worker? There's just no template for it. It's days of work to get it over the line.
"Ownership is so easy, imagine if you not only have to work, but also have to deal with ownership problems such as maintenance, insurance, business and real-estate, logistics, marketing, depreciation, and management. - and, best of all, you don't own any of it if you stop working!"
The material suppliers and toolsmiths also own the fruits of their labor, and don't owe them to you.
Capitalism exists because individual worker ownership doesn't scale beyond simple trades. If a worker gets enough wherewithal to scale his or her operation to just a small shop, there are going to be workers there, who are either wage labor, or else customers who pay to use the shop.