Well, back then Atlas, Polar, World, Kalitta, Gemini etc etc etc was doing that.

Not starting a comparison between an expat job and a domestic one. Just pointing out that many of those same boxes could be checked off without leaving the country for a job to do it. And back then, many of those places were simply considered stepping stones as well. Crappy pay/workrules compared to now on a relative basis.

I am looking to apply at Eva, and one of the requirement is a 5 years of employment reference from aviation industry.
Not sure what is exactly means.

They want to talk to your supervisor, chief pilot, director of operations, A/C owner....... Anyone who can give them references from your performance as an employee and they want to go back as far as 5 years (most of the applications I have seen want a 10 year history, make sure the time frame is correct) if you have been employed at your present job for more than the 5 years they are looking for then only one reference is needed, if the company no longer exists and no person is available then specify when it was closed down and so forth.

Thanks for the help.