The whole concept of programming languages has not changed that much. We have the two big pillars that is the Turing Machine and Lambda Calculus (and various others) Everything after that has been abstractions, and when the abstractions are good, we call them paradigms. But it's all abstractions, and ultimately we are just writing instructions for a really dumb machine to compute data for us.

> Why do I need to worry about small language specifics like brackets, terminators and so on when tools should be able to auto-complete them for me?

Because the computer is something really simple, and the programming language is just a idea conduit from your mind. Those delimiters are as important as the language keywords, because they are part of the RULES. Auto-completing them will require more RULES and more delimiters.

> You're editing a file (or parts of different files) and are focusing on say 5 methods that are interacting. I want to see all of them on the screen at the same time

Vim and Emacs. Or Smalltalk IDEs like Pharo

> Data conversion

Vim and Emacs macros. But the truth is data encodings are very important, because for the computer, it's all bits, we assigned meanings to these bits and enacted RULES that describes how to manipulate them according to these meanings. Morphing from a set of RULES to another will require more RULES.

I will urge you to try a live programming environment (SLIME for Common Lisp, Pharo for Smalltalk, The web inspector for Javascript (not great)). It feels like working on a boat in the middle of the sea instead of having it on land imagining what it feels to sail it.