You should really read the literature you try to post. From the abstract of the study the article cites (~and the article itself implies agreement with~):

"Overall the findings suggest that, with the exception of female-sex-related slurs, taboo expressives and general pejoratives comprise the core of the category of taboo words while slurs tend to occupy the periphery, *and the ability to generate taboo language is not an index of overall language poverty.*" [* Emphasis mine]

Edit: realized the article does make the distinction between the ability to generate profanity and the willingness to do so, which while interesting is mere conjecture propped up by an anecdote within the article. I contend there are times for profanity and times for avoiding it, but suggesting that because someone chooses profanity they must be less intelligent is perhaps a comfortable idea, but it may also be an elitist one.

Swearing linked to more intelligence, not less [1]

[1] https://www.sciencealert.com/swearing-is-a-sign-of-more-inte...