Steward-ownership is a philosophy more than an actual structure, my understanding is that each such company is in practice structured somewhat differently.

This article explains roughly how Patagonia is structured: https://medium.com/@purpose_network/the-patagonia-structure-...

For Patagonia a trust owns 100% of the voting rights, while a charity collects 100% of the dividends. I don't doubt that there are ways the structure could be subverted, but it's a far cry from "money without oversight".

Do you have examples of Steward-owned companies that ended up with "well, we might as well spend the extra profits on executive benefits"-issues?

(I personally think Steam should go in that direction, otherwise I'm afraid enshittification is unavoidable once Gabe Newell is no longer at the helm)