Assuming blockchain (and OpenSea atop that) count as "no middleman, no overhead" and not a new middleman (but it's a good one, because Andreessen Horowitz will make bank if it succeeds) atop technology that requires more energy consumption than small countries, it still isn't some magical wand that creates more people that spend disposable income on art.

Commissioning art is one of _many_ ways you can do this. Non-commissioned works are readily available too! I also purchase those! Some of these are one of a limited set (common for photo prints), some of these aren't (Bandcamp albums). Point being, if you were someone who wanted to buy art before NFTs, you could do so. I'm skeptical of there being some large market segment that desperately wanted to buy art but only realized they could with the advent of NFTs.

The royalty business model also already existed, where it made sense. There's no contract governing me reselling the painting I bought from someone at the local farmer's market because there wasn't any expectation on either my or the artist's part that it'd be resold at all, much less for a sum vastly greater than its purchase price. It's going to hang on my wall until I die, at which point it'll likely get tossed in a bin.

That's in contrast to say, a film score, where the expectation is that it will be resold (as part of your theater ticket price, but whatever) many times over: ASCAP exists, and handles paying the IP lawyers on behalf of its members, because that's a business model that works for them. They've been managing this just fine for over a century.