Paul Graham's Quote on the Biological Basis of Intelligence

So, I just came across Paul Graham's quote on Twitter :

" I wonder if, as the biological basis of intelligence becomes better understood, it will start to seem wrong to call people stupid. "

Does he mean that it is ok to call people "stupid" in their face if they have a low or average IQ ?

Also, what is Paul Graham's IQ ? Is he a genius ?

Can we work hard in our lifetimes to increase our IQ significantly ? For example, if I study very hard and practice 10-year series's for Mensa tests, can I increase my IQ significantly. For example from 100 to 130 or something ?