This is a myth, and even if it were true, the small-time inventor in that scenario is just as much of a barrier to human progress as the large corporation that will inevitably gate-keep the invention and extract every drop of profit they can from it for as long as legally possible.
Patents are just a way to kneecap you and all countries allied with you when compared with countries that don't honor those patents.
The same goes for IP in general, but that's a whole other can of worms...