I'm a computer programmer, and encounter plenty of people with "various credentials" from "various nations".
It may be frustrating and annoying, but thats life.
However, I'm also a Private Pilot, and what truly terrified me in flight school was the foreign students who came to the USA to start on their Professional Pilot training, and cheated their way through the tests. They cheated through the written tests simply because they were goofing off and not paying attention in class.
The tests were entirely fair and passable if you paid attention in class and did the homework. But they chose not to, cheated through the tests (were occasionally angry when they were caught.... they were *paying* a lot for this education! Didn't you know... they *deserved* to pass for how much they were paying!)
It wasn't only the pilots. Several studying to be aircraft mechanics (in another class) were also caught cheating.
I know a student from a Air Traffic Control program who had several Chinese nationals in her class, and they were cheating their way through.
(not just a few questions or a few percentage points... but wholly cheating on entire exams).
Much of Asia likely has incompetent pilots flying improperly maintained aircraft, and directed by incompetent Air Traffic Controllers. I will never fly over there after what I saw.