I once looked at a job listing for something with very specialist technical knowledge in specific programming areas, for a Japanese company based in Tokyo (pre-covid so remote wasn't really a thing yet). Pretty niche stuff and needed at least basic Japanese language skills too, so I assumed it would pay ok - even if it wasn't good or great in comparison with jobs where i was.
After conversion it worked out to be around USD$40k a year, which is probably just over 1/3 of what it would pay at minimum elsewhere. More like 1/4 or less for Silicon Valley type locations, but the rent for a tiny Tokyo shoebox is about the same price even if food is a cheaper. There was no way I was applying for that.
It isn't just about a weak yen, it's much more about hugely underpaying people.
Yes, unfortunately i think you've missed a few things.
Anyone can be sued for anything, whether the suit is successful depends on validity and damages
It would be difficult to prove damages in this case, but you don't need to sue anyone anyway
Only businesses and organisations serving the public are required to follow the ADA
The government, if it received enough
valid complaints and received a negative reply from a place which needs to follow the ADA might consider bringing legal action or enforcing penalties
Common practise does not exclude the possibility that something discriminates against people, which is why these rules were written