I don't think the lack of scientists is the issue. The issue is others providing all the engineering and support that scientists need - to survive in the first place, and then to get science done.

If you want to continue your example of sacrificing a child, a more effective proposal would be to have extra children and bond them into near-slavery, taxing them at some high amount so as to support those who do science.

But that would be a real sacrifice, and most would not find the idea pleasing.