Dismissing an argument/complaint because compared to something else it is small is simply stupid and makes me lose respect for anybody that does it. amirite?

Yeah someone else's misery doesn't negate my own. Although, if one is thinking in terms of resource allocation I do think someone starving deserves more immediate attention at least than say a person that's failing school. There's a reason people say stuff like this and it has to do with sizing up the problem at hand..not to dismiss someone's pain or needs but to put into a wider perspective..choice for instance is a first world problem..many people in developed countries struggle with choosing what to do with their life and it sometimes feels silly when you look at people elsewhere who would kill to get even one choice. But this is a clear example of inequalities and they should be compared. Also, if a friend calls me complaining about a breakup and I have a sick child at home then yeah I'd probably be indifferent to what they are going through.

Relative Privation Fallacy if you wanna be fancy

This isn't necessarily unpopular. That's why the kid in africa meme exists lol. But I agree with you

Whataboutism

There's always a bigger and smaller fish its a glass half full/empty thing

yeah this kind references a joke comedian Joe Machi said paraphrasing but like "telling someone, someone has it worse so you should be happy is like eating a sandwich in front of a hungry looking homeless guy"

My understanding (and I could be completely wrong about this) is that the 'starving kids in Africa' thing was just a hyperbolic way to call someone out who complains about something trivial. To be fair I haven't actually heard that phrase in like 20 years.