Maybe an analogy of "why not solve all medical problems at once" is closer.

We absolutely want to, of course. But you extinguish an industry and the systems of training that supply it. It's hard to know if letting it go that way is right.

Why not cure cancer and take care of the researchers’ kids?

The point isn't what happens after something is solved. Where is the motivation for humans to study/find a potential solution if your kids are going to starve while you do it? These things can brute force problems that have a clearly and feasibly searchable answer, but they can't make creative leaps. It will be a severe dark ages for mathematics if humans stop contributing.

You have misunderstood.

I have a the cure for cancer. Simply kill the host. Does it work? Yes. Have you learned anything from it? No.