So, I recently learned about this from my company's patent lawyers

By your company's patent lawyers' logic then, any American drug or technical doodad patented in America is totally legal to be knocked off in Majarashtra or Taiwan or Guangzhong. Pretty sure if you tried pulling this you would be disappointed with the outcome. Not that it is not done (obviously), but that it (pretty sure) isn't legal.

You are talking about the Paris Convention. The parent poster was talking about the Patent Law Treaty. The Paris Convention made it easier to file in other member countries after filing in your home country, but you still have to file in each country you wish to be covered in. The much newer Patent Law Treaty allows for "international" patents, which only need to be filed once to be applicable in all member countries.

I didn't realize that, thanks! After looking at Wikipedia for a bit it seems there are two phases under the PCT, an international phase that is sort of like the main part of a patent application, and then the national phase that actually creates the patents in each region/nation based on the first phase. The first phase is like what I had in mind: You file once in one country but the results of this filing apply everywhere. So as I understand it you don't have to do the full process everywhere, but you have to actively register everywhere where you want protections. And there is no automatism to the second step(?) https://www.wipo.int/en/web/pct-system/faqs/faqs