As a child you learned through social cues to immediately put out of your mind any idea that cannot be communicated to others through words. As you grew older, you learned to automatically avoid, discard, and forget any thought avenues that seem too difficult to express in words.

That's not a sufficiently weak version. To me this claim looks like the conjunction of:

The strongest formulation of the Sapir-Whorf hypothesis (disproven)

That people have an aversion to thoughts that could lead to things not expressible in words

That this is not an innate property of language use, but is caused by social pressure

The last one seems almost plausible (autistics are more likely to have thoughts they can't express verbally and to ignore social cues-- is it correlated in the general population, or do those just happen to be the result of autism?), but in that case is only true for specific readers.

As far as I know (and the last that I checked), there's only been one study done on trying to teach the Pirahã to count. Have there been others, or was it just a fluke?