Why is everyone on reddit so mean?

I'm genuinely curious, though. Maybe I'm just not a very unfiltered person because of the environment i grew up in and find being so blunt with strangers kind of rude but why?

I posted a question on reddit to get answers obviously. It was a very simple question. I want to know about [thing]. I did my research but wanted people who are more knowledgeable about said thing to tell me more and I just had these angry people in my replies telling me I'm a child and don't know how to do research and if i don't have years of experience my book will be shit and not well written (I asked the question because I'm writing a book and wanted it to be accurate).