I completely agree with you. Sure, you don’t need expertise to help. I do try to help people if I know I can. There were instances when I told people about a few things they could work on, and I got responses like “Who do you think you’re?!”, “Stop showing off”, “It has got a lot of likes on it. So I don’t think I have anything to edit” etc. A writer must first listen to his critics and see if any of that is going to help them get better. Offering help doesn’t mean I’m flaunting my skills and there are people who get offended by this. And that’s why I prefer minding my own business. Unless someone asks me to critique, I don’t do it.