Ask HN: Why so much complexity in modern frontend development?

Today I've stucked with a question, am I doing it right in frontend? There a lot of abstractions on top of simple DOM, why do we need them? Why is it getting popular? For example, lets take Angular, it's a world full of abstractions, why it so complex, why not to use some patterns, use perfectly designed native browser API's, and use some patterns for structuring, organization and refactoring? Why javascript is getting much complex than it is?