You are under this illusion about other fields like architects because you don't work there and you can't tell. You don't know how the sausage is made.
Historically I have tended to learn about a new field WAY too much before I tried to hire people in these fields. The truth is, that makes it hard to hire people (but for good reason - depending on your needs, you need to pass on a lot of people). More recently I have tried to pay very close attention to how people do their work (about whose field I am building an interest). The sad reality of the world is that most people and businesses stay in business entirely through dumb luck and because the world is not usually THAT demanding. And if you have a specific requirement, they won't be able to help "out of the box".
You are imagining this competence. It doesn't exist in most people.
And to compound this, to me, the characteristic of an engineer is that they are capable of learning about a specialty discipline. If you hire an engineer and they are incapable of learning something that's needed in your project, THAT is where their problem is (and yours for not hiring to that.) Engineering is not a trade. Certifications are usually about selling them or gatekeeping. I wish it were possible to certify "engineering progress mindset" - no, it doesn't have an ISO number.