Isn't that just a rephrasing of the Sapir-Whorf hypothesis? If so then it's old and thoroughly debunked. Language features don't seem to influence the way we think, which is another way of saying that intelligence and language are different things. If you want to read about it you can look at the history of this idea in the 20th century from when it was proposed by linguists in the 1930s all the way up to the time it became discredited, as there are many research papers and even books on the topic.
One of the really troublesome problems with Sapir-Whorf and derivatives is that they led directly to some very nasty totalitarian behaviors. In "1984" a core policy of the Big Brother government is Newspeak, in which language changes are (believed to be) used to control the thoughts of the population and establish eternal power for the Party. This wasn't merely a quirky bit of fictional sci-fi, it was directly inspired by the actual beliefs of the hard left. The extent to which Newspeak was an accurate portrayal of life under the Nazis and Communists is explored in "Totalitarian language : Orwell's Newspeak and its Nazi and communist antecedents".
https://searchworks.stanford.edu/view/2016479
Today it's known that Sapir-Whorf isn't supported by the evidence, but there's still a strong desire on the political left to manipulate thought through language. Stanford's recent "Elimination of Harmful Language" initiative is a contemporary example of this intuition in practice. It doesn't work but it sounds so much easier than engaging in debate that people can't let it go.
tl;dr to the extent this has been studied already, intelligence is not in the language.