I'm fairly certain they're mostly laundering schemes at this point -- half of the tech founders I've seen seem to be pitching MVPs that could be readily found in any CS undergrad's Git repo lol.
Sure the core technology, right now, might be "obvious", but a company is so much more than the tech. Without a story, marketing and sales, the company is nothing!
The founders might be bringing connection, validation of the product, LOIs, etc. All of which are much, much* more difficult than the tech.
*usually.
Jokes aside, oftentimes, the most disruptive technologies are not actually technologically difficult. If we take a look at the early days of mega corps today, most of them found an edge in an emergent market with off-the-shelf tech stacks.