The only fix for that is discipline. You can't automate away quality. The best people/teams understand that and make good docs a feature requirement, not an afterthought.
My favorite example is Stripe. They've never skimped on docs and you can tell they've made it a core competency requirement for their team.
The one lesson I have learned over my career: Don't work in teams (or for managers) that rely on discipline to get things done. Every time I've encountered them, they've been using it as an excuse to avoid better processes.
Sure, some counterexamples exist. Chances are, those counterexamples aren't where a given reader of your comment is working.
No, you just need to both understand how your system works and then clearly write down what it's doing and why. If projects like Postgres and SQLite and musl libc and the Linux kernel can all do it, I think the CRUD app authors can do it, too. But it's not magic, and another tool won't solve it (source: I've seen a hundred of these tools on scores of teams, and they don't help when people have no clue what's happening and then they don't write anything down).
"[docs] will take an example and do something with it to demonstrate an outcome."
No. Good docs will explain the context and choices made and trade-offs and risks and relations etc. All the things you can't read from the code. API docs can to a great degree be auto-generated, but not writing the _why_ is the beginning of the end.
I wonder if there's some conservation law for "concerted mental effort." As if by spending time and energy on the often exasperating task of keeping documentation relevant, you reduce the time and energy required to comprehend the system.
You're right, it is a matter of culture and discipline. It's much harder to maintain a consistent and legible theory of a software component than it is to wing it with your 1-2 other teammates. Naming things is hard, especially when the names and their meanings eventually change.
My favorite example is Stripe. They've never skimped on docs and you can tell they've made it a core competency requirement for their team.