What style is that? The style of composing persistence technology, Authentication and Authorization, dependency injection, messaging, web communication etc to make a business application? If you know of a magical tech that doesn't aim to solve these problems in a standardized modular way so that the developer isn't socket programming from the ground up then please chip in.
"There are many moving pieces and many permutations of how they interact together."
Agreed. The problem space isn't todo apps or "Hotdog/No hotdog".
"It's practically impossible to understand it in its entirety, and thus impossible to guarantee that it's secure."
I don't understand the finer points of the myriad of TLS cypher suites etc, probably means I can't guarantee that they're secure. But what other option do I have? roll my own? Nope I'll take sensible defaults and twiddle the knobs where the client's requirements demand something different.
"You're basically plugging holes as you find them, but you're never sure that there aren't more holes you don't know about." - this is FUD.