Yes you can build it in a single prompt, but you miss the 93 versions of iterations and thoughts of the developers who've already made the project. If you have the money, why not buy a product/team that already has a year of experience with real users instead of reinventing the wheel?
That is your assumption. I am not talking about one-shot. I mean that lots are people are going through more iterative development cycles than ever in the history of software. Just my own examples (100% agent written)
https://github.com/brainless/nocodo, https://github.com/brainless/dwata, https://github.com/brainless/akar, https://github.com/brainless/baho
All these and more, from a single engineer with 3 x $20 subscriptions. While I also run chicken and pig farms. It will take time for people outside tech hubs to understand what LLMs enable.
Not that I don’t think there’s amazing things that can be built easier, but designing and building a product is more than writing the code. Look at where you spent effort for your own examples. There’s a skill there which goes further than just reverse engineering an existing solution, and that skill is obviously of value to Meta. People were going crazy for the price they paid for instagram some years ago I remember.