> first time they bumped into a problem with not having a degree is when they wanted to take a stab at working in the US, because there are visa requirements and suddenly that paper is no longer meaningless.

Regardless of "working in US" is in OP's future (or 'dreams'): NOT finishing uni will close a # of doors for you. Which ones? You'll only find out when it's too late to do anything about it.

Many young people won't even have a chance to attend uni. Or succeed - because eg. their previous education was subpar.

That puts you in a privileged position. Be thankful for what (opportunities) you have. So if at all possible: graduate. Decide whether it was worth it afterwards.

The idiosyncracies of grading systems etc: just another case of RTFM. Deal with it & move on.