The market has been distorted by endless amounts of VC funding for very dubious ideas that would never be profitable to begin with, so now you have 2 solutions: you can spend a few hundred grand building a boring solution with a slim amount of engineers, realize it doesn't work and quit, or you can keep over-engineering indefinitely, keep raising more and more millions, enjoying the "startup founder" lifestyle while providing careers to unreasonable amounts of engineers with no end in sight because you're too busy over-engineering rather than "solving" the business problem, so the realization that the business isn’t viable never actually comes.
Which one do you pick? The market currently rewards the second option for all parties involved, so it's become the default choice. Worse, it’s been going on long enough that a lot of people in the industry consider this normal and don’t know any other way.
I've commented/ranted about this before, see https://news.ycombinator.com/item?id=30008257, https://news.ycombinator.com/item?id=24926060 and https://news.ycombinator.com/item?id=30272588.