I think a good mindset for building modern javascript apps is that they are full featured desktop / mobile apps, just like a windows / mac / ios / android nativ

I think a good mindset for building modern javascript apps is that they are full featured desktop / mobile apps, just like a windows / mac / ios / android native app. By definition these types of apps are complex, and always have been, but they are highly valuable! Looking at it from the lens of "web apps are just some html and css with a little jquery" is a mindset that can make building very ambitious web applications seem disproportionately difficult.