I just inherited a React project that was full of these mistakes. The code was littered with "onClick" and "history.push". They used MobX because they wanted a

I just inherited a React project that was full of these mistakes. The code was littered with "onClick" and "history.push". They used MobX because they wanted a store, even though they didn't need it. Components would often receive this store as a prop, instead of just the values it needed to render. So yes, these mistakes are very common. There's just quite a few ways to do things, and if you don't do any research, they all have the same outcome.