The vast majority of software being written today is still CRUD applications centered on a database using a groupthink architecture where every noun gets a table and everything you ever want to know about that noun goes into that table. They're extremely brittle, completely un-reusable, and virtually un-maintainable. Meanwhile the front-end tech is iterating rapidly because we're at the very beginning of that sigmoid curve, not toward the end. Software engineering is still very much a baby discipline. We are brand, brand new, and not
nearly as advanced as you seem to think.
Meanwhile Bridge Engineering, a 4000-year-old discipline, is still inventing new ideas and is still done almost entirely by human engineers. They use computers to multiply their expertise, but in no way are the computers "designing the bridge" for them. Why would automation make software engineers obsolete when that hasn't happened to bridge engineers (and shows no sign of coming)? Apps have been "building themselves" for decades: it's called a compiler.
How do you manage complexity? With software engineering. Writing software without writing code is like trying to design a bridge without doing math.
And if it's those crappy, un-maintainable, un-reusable CRUD applications you're saying no-code will replace, then I say: good riddance! But even if no-code is more successful than its wildest dreams, it's still just automating that lowest tier of programmer. Meanwhile, better abstractions, programming languages, type systems, mathematical advances, training programs, techniques, and architectures have been raising that water level every year for a long time. Even a good no-code solution has a very limited expected life when it's competing with that.