Note : the mini-research methodology is not particularly scientific, but, in my opinion, practical. To me, the results seem interesting and useful, but do not consider them to be the ultimate truth.
In general, the result is eloquent - runet authors who write in English for every 20-25 words have an error, while for foreign authors, grammar checking software generates recommendations (that is, these are not even necessarily gross errors) once for 30-40 words .
Another conclusion is that it’s more difficult for us to write accessible texts. This is a common "disease" of non-carriers - I want to "wind up" the text more seriously, as a result, it is difficult to read.
That is, foreign authors write shorter, and their audience gets used to reading texts of this particular format.