I think one way to define math is “the collection of symbols we use to precisely explain natural phenomena”.

I can say “that rose is very pink” and that is accurate enough for most people. But if I want to know how much pink there is in the rose, I need a better descriptor than “very”.

So in that sense, Math is made up. It’s just the language we use to describe stuff when spoken/literary languages are imprecise.

But it also isn’t made up because there are objective justified truths behind its symbols. Aliens would probably have the same concepts, they’d just use different symbols.