I think the core problem is that Reddit’s leadership wanted it to be an SV unicorn, and they tried lots of ways to make money off the site (cryptocurrency, Reddit gold, an official app that I swear was designed to make you click on ads by mistake, etc.). But it as never going to be the kind of cash making machine, actual or potential, that they were looking for. Well, that and, once you start taking outside investments (especially from VCs), the goals of the organization necessarily change towards making an exit (IPO or acquisition).
I think this essay gets at a lot of the things about how the place worked and why the value was hard to convert into money. The feudalism frame is a little gimmicky, maybe, but does provide some perspective and a useful analogy.