You're not getting high budget shows without like a hundred million subscribers, sure, but there are bootstrapping options.

Dropout does their original content on around 1 million subscribers @ $6/mo.

There's also licensing existing content -- the mega corps building walled gardens aren't likely to play ball, but if you make it painless and have non-exploitative terms, there's countless smaller content producers who would happily upload their catalogue to another service.

I think if the right group of founders (experience in streaming,v experience in content production, good professional network with existing smaller production companies) was able to kickstart it with a million subscribers, give or take, they'd have decent odds of providing enough value to start a more subscribers -> more content spiral instead of the reverse.