If you don't like a work, you don't have to play it or comment about it. The author may need some more experience to reach your level of reading comprehension, but that's no reason to be an asshole. I've proofread things for dozens of people and lived in nations where English isn't the first language, and I've learned not to throw shit on others' writing even though mine is at a much higher level. So you, too, can be respectful of the author and provide constructive criticism or else just sod off.
Constructive criticism is anything that will help the author improve their game. Learning English will improve their game immensely, as the game is written in English. It is highly constructive.
The author not feeling like doing the thing you suggest doesn't make it not constructive. Especially since I would obviously have no way of knowing if they feel like doing it or not before suggesting it.