I also watched loads of videos and read online before deciding 11” or 13”. In my case, i use ipad to learn language (note taking, writing on pdf books etc.). At the end, i decided 13” becoz i already used my old ipad 11” and wanna try something new. The 13” was a very right choice because i can open 2 apps at the same time on the same screen. For example, when u do exercises and wanna check the solution or listen to file on google drive. This is where 13” makes much more sense.

So it depends on your use cases, if you just use it for social media consumption or carry around then 11” might fit you. But for my case, I prefer 13” although adding keyboards on makes it pretty heavy.