Let's say you have a dependency A from China. But all the software developers that work and specialize in A, live in China. If you ban dependency A, what you'll have is a dependency B from Mexico that is calling dependency A.

In order to really replace A, you'll need to hire, train and form software developers specializing in A. This is both time consuming and expensive.

This falls in the same line of some people (economists) who think that printing money will generate wealth. Sounds familiar?