As a non-English living in a country where English is not even an official language, I strive to write good quality answers, either technically or in grammar. A good answer takes an investment of time to write. If someone is not willing to take some time to correct the English and research an answer, it is natural low-quality answers are not welcomed. It takes less work answering them ourselves than improving bad answers. Furthermore, what the owners are asking is that 90% of the users take care of the 10% that generates noise for free, and are telling the majority of the user base there are others that are more important than them.