IQ tests are not culturally biased. This is a decades out of date canard. Some tests, like Raven's Progressive Matrices, don't even require the test giver and taker to share a language. IQ, as a statistic, washes out almost every other psychometric in predictive validity -- there are a staggering number of psychology papers which pointedly do not include IQ because whatever predictive power their metric purports to have is totally overridden by IQ. There are many subfields of intelligence and two major categories (fluid and crystal) so it's true that intelligence can't be defined as a single number, but this is a strawman since intelligence researchers have never said this.