Perhaps because it is genuinely less important on the pyramid of human skills. Reading, language comprehension, and critical thinking are more universally needed than, say, matrix multiplication or integrals.
2. I may be biased, but I believe math is distilled critical thinking. The difficulty is teaching math critical-thinking-first as opposed to test-first.
I actually think this is likely not true.
If you were to take an 18 year old who can't read, and another one who can't do addition, which do you think is less employable?
There's a lot of jobs one can do without any math. Almost none one can do without any reading.
There's more to it than all this of course, but I think literacy is the clear winner compared to numeracy.
The person who can't read can be a traffic guard, server (with the right cash register), bricklayer, or any of a number of jobs. However, all of those people need to know that they worked X hours @ $15/hour and should be paid 15X. Otherwise they will never know if they were ripped off or be able to plan for the future.
That said, addition is a very low bar--I cannot think of a single job that would not require at least basic addition.
Based on current wisdom. Current wisdom has a spotty track record though. It was once an obvious truth that reading was only for a select group. Universal literacy would have been as absurd back then as the notion of universal math literacy is now. Which is depressing, because one would hope that at least this historical analogy, and it’s implications, had occurred to more people.