That is not a mistake native speakers make with the same persistence.

What interests me about that recent podcast mention of "disingenuine" is that it's a different kind of error from the ones Korean learners are told to fix. A native speaker swaps one word for a similar-sounding one, and the meaning is still clear. A learner who writes "I am agree" has built a fossilized structural error that, if left uncorrected, will appear in every future piece of writing and signal a lack of basic control over the language. The two are not equivalent.