Because native speakers are much more likely to use English every day and therefore much more likely to successfully remember how to spell "successfully"?
I'm not sure why you think that part of the comment was controversial. Certainly you would agree that the vast majority of people who don't natively speak English would be unable to spell such words as "read"?
Native speakers don't necessarily use their native language every day, and in fact a non-native English speaker might use English every day.
There are cases in which non-natives might have better grasp of orthography compared to natives (which might be what GP is objecting to).
I'd be surprised if the vast majority of non native English speakers would fail to spell "read"... Otoh as a non-native, I struggle to be understood and properly differentiate letters like a-e, p-b, etc. So for that reason I use the Nato alphabet whenever I need to spell something
I don't think you understand the difference between "likely" and "guaranteed".
> There are cases in which non-natives might have better grasp of orthography compared to natives (which might be what GP is objecting to).
Certainly. Neither me, nor the "GP" to which you refer ever said anything to the contrary.
> I'd be surprised if the vast majority of non native English speakers would fail to spell "read"
Really? Depending on how you pronounce it, if they even spelled an English word, it would be "red" or "reed". Are you trolling? You do realize most people who aren't native speakers of English don't speak any English, right?
I'm not sure why you think that part of the comment was controversial. Certainly you would agree that the vast majority of people who don't natively speak English would be unable to spell such words as "read"?