Um.
Ever wondered why the USA is now verging on a third world country? It is because its education system is now so low level that people cannot thinkl straight. I couldn't believe the level of ignorance in your country when I immigrated there.
You don't have an education system. When I returned to college in my mid-50s, I was appalled to find that I was being taught stuff that I learnt in years four and five in junior school in South Africa in the 60s.
In those days, we had a three tier education system. It worked. People who were better with their hands then their brains went to trade school. If you weren't brilliant with your hands but had a reasonably good intellect, you went to college. If you were brilliant intellectually, you went to university. College and university were different things.
So, yes, learning modalities are different. And, yes, people have different abilities. However, to confuse problem solving intelligence with the ability to sing or dance or paint or whatever else is sheer intellectual dishonesty.
Nobody disputes that different parts of the brain are used for different skill sets. Nobody disputes that people are good at different things. What you (and Gardner) are really trying to say is that one is not less human or unequal because one's intellectual quotient is higher than others.
Why can't you live with the idea that in a high tech, science based society, there is only really one type of intelligence that can keep it going. Without that particular type of intelligence, we would not have our modern world.