Only when you modify extension code, not pure Python code. So my experience is a bit different: I have one command to type when I modify extension code, yes, but that’s the regular experience when modifying any kind of C code (including outside of the Python world) – modify C code, then recompile. When I only modify Python code, though, I don’t have anything to type.
I will add that some extensions can be slow to build, so not having to re-run pip install every time I modify pure Python code is really important.