I have a friend (of 20 years +) who is Sri Lankan.
Looking to treat him to a trip. Even in SEAsia the ability to get a visa is extremely limited. There seems to be a magic number of $US1000 in your bank account. I suspect it may be impossible for him to get an Australian visa even though he owns his home and would have all family remaining there. Perhaps we'll see.

A college class mate has had the same problem when trying to arrange trips with a Vietnamese friend... though the SEAsia choices are less limited than my friend's.

There are definitely levels of discrimination. Yes NK and Cuba may prevent their people from traveling by not issuing passports - but even with a passport the citizens of many countries will still find very few places that will permit their (legal) arrival.

Happy wandering (if you are permitted to)

Fred