Bear with me on this, as I may be a little out of touch. I cannot stand tiktok, facebook, youtube, and instagram, so there could be some innovation I am unaware of, but I thought content creators published content on their channels and the platforms gave them ad revenue share from all the views they generate, plus additional income from paid subscribers for paywalled content. I am mostly aware of how youtube works. Out of 2.49 billion active users on youtube, the channel subscribers who 'directly' pay content creators for memberships are only 100 million, which is about 4%. Memberships tend to be from $1 to $50, but most often are about $5, and of that 30% goes to youtube. So, unless you have millions of views and play a ton of annoying ads, you don't make much. Also, just few video content creators make quality educational or entertaining content (which AI can now do in minutes), while the majority is mindnumbing crap that is toxic and should not exist, but is easier to create and appeals to people's lizzard brains.
So, do we need a cambrian explosion of crap content on Nostr? Do we even want Nostr to become youtube, why? Without ads on Nostr, content creators won't make much. Only 4% of 2.49 billion users pay content creators. 

You mention: "Some of them charge $3-5k a year just to get access to this closed space, and people are willing to pay for this."
What does this mean, where is that?