That the person above didn’t bring a solution does not invalidate their statement. Immigration is only a solution for those getting the immigrants. It’s not so nice for the countries that raise and educate them without any ROI.
If somethings broken and you can't fix it, then you either learn how to fix it or you need to accept that it is broken and move onto something you can fix.
P.s. I really like the engineering analogy, but remember when discussing politics: other people have probably already defined the problem and come up with solutions. As a citizen, we need to choose which solution is best; or promote our own solution.
That's what 'export led growth' is. It just works by hoarding money as 'foreign reserves', rather than using protectionism.
The entire world can't be using 'export led growth'. There has to be net importers to balance it out. Which currently are the US and the UK - the current and previous imperial nations.
Edit since I'm getting downvotes: I'll take a stab and hopefully someone will correct me. Do you mean a return to Mercantilism? If we can't have immigration because that is 'taking another nations resources,' then we must end up with some kind of Protectionism or Mercantilism? Or are you proposing a World Government?