I land in the "if you need an IDE, you already took a wrong turn" school of thought, basically Paul Graham's position in this old post: https://news.ycombinator.com/item?id=72710
granted, we don't always get to choose what language we use or what code bases we inherit.
That's a very strange attitude from someone who proselytizes Lisp, the language which pioneered IDEs about 30 years before other languages really had anything comparable.
Emacs, for Common Lisp, is still a much more advanced IDE than many languages have. It used to actually be a significant ingredient in the secret sauce that made Lisp so powerful - an advantage which it has thoroughly lost to IntelliJ/Visual Studio in my opinion.
There's a school of thought that Slime in Emacs is such a different beast from what is generally considered to be an IDE that it doesn't belong in that category. My guess is that pg belongs to that school.
I guess that is because Emacs is just a fraction of what Common Lisp environments are capable of, so what gets happy with what they can get (as free beer).
granted, we don't always get to choose what language we use or what code bases we inherit.