Are "first world problems" still problems? Do they matter?

Obviously, some of the things written off as first world problems are truly trivial (like having to go all the way to the back of a grocery store to get milk). But more and more, it seems like anything that isn’t an existential threat gets the label “first world problem.”

Not everyone has the luxury of owning a horse, but it seems like a real problem if your horse gets stolen. And not everyone has access to modern technology, but it seems like a real problem if some piece of technology doesn’t work the way it is supposed to.

Are these things real problems? Would you refer to them as “first world problems,” or do you reserve that label for the truly trivial things like accidentally opening a box of cereal at the wrong end?