No one was being rude, they're actually trying to help, if you thing that comments like the ones you mentioned are rude, then your interpretation is wrong. And for your information, not everyone reading this manga is a native English speaker, so is very hard for us when is bad translated like this, the translator could have of asked for help before publishing it because that's what you do when you are writing for other people, you ask for opinions first.
But they aren't helping? They are just complaining and criticizing? Some offered to help but most are just makin crude comments that show they aren't appreciative
It's normal to have negative responses, not everyone is going to like what you do and that's okay, we all like differents stuff, so don't feel bad on behalf of the translator, because the translators and even authors are prepared for those kind of comments. You know what they do with those responses? They read them and get even better at what they do.
Someone is taking their time to translate the story so we can actually get a sense of what is going on and instead you give backhanded compliments like "It was hard to read but thank anyway" and "the translation wasn't good but thank you" are you serious?? You think your understand it better if it were in Chinese? The answer is no. Just say thank you and be done with it don't try to criticize someone for something you can't even do