This is a tragedy. Why do people keep reinventing the wheel like that? Why don't we just have one system/app that does everything (buy/sell books, find roommate

This is a tragedy. Why do people keep reinventing the wheel like that? Why don't we just have one system/app that does everything (buy/sell books, find roommates, cost splitting, etc.)? Hopefully what I'm suggested is not step 11: https://xkcd.com/927/ https://xkcd.com/927/