One of the tricky things about worker coops is that it’s more difficult to grow fast. You can’t just have outside investors and shareholders pump money into it. Ownership and employment are directly tied together.
There are successful software worker coops out there. Usually small and medium.
And there are examples of firms that follow the spirit but not the legal structure. Effectively worker owned, but regular corporations on paper.
Generally worker coops have been shown to provide more stability/sustainability, worker engagement in many cases.
My intuition is that these virtues are less in demand than rapid growth and big exits when it comes to software ventures. Also a big issue might be that this business form is simply less on the radar for people, which can be perceived as risky or off base.
But there might be domains and types of projects that would fit very nicely.