While I agree with your statement, the way your sentence is structured, probably because of the fact that it's not your native language, makes it sound quite rude and condescending. I'm sure there are many better way to express that opinion in a nicer and more constructive way.
@@glitterglamerous96 "Why you guys can't understand what she's saying?" can be simplified to "I can so why can't you." A little bit condescending to say the least. "If you don't understand go back to N5 level.." is the case of gate-keeping; If you don't do X, you can't do Y. You're pretty much gate-keeping people from learning something, not the best thing to do to be honest.