I have no idea how they operated, but he may have originally been funded by venture capitalists or angel investors. That money does tend to dry up once you have gotten off the ground and they realize that you do not have a viable business plan or a way to ever make a profit. Twitter has lost billions and billions of dollars for years and years on end. It obviously would have gone out of business if it wasn't politically useful to shape public opinion. Powerful people keep Twitter alive with cash injections. Parler didn't have that luxury. It makes me wonder how long they would have been able to operate in spite of the lack of web hosting before they ran through their funding.