I always take a full disk snapshot before full upgrades like this (boot into recovery and this is straightforward with a usb disk, or use carbon copy cloner) but yep updates in the Apple eco system are (knock on wood) very painless.
Back in the day before things like homebrew it was far worse... the days of macports and mod_python to run your Django app are fortunately behind us.
MacPorts has a pretty slick migration feature now. Not sure about Django, but this is the smoothest migration I've experienced with MacPorts in over 15+ years.
Times have changed completely since... 2006-2007 when this was relevant. If you are still using mod_python in 2024 please seek a therapist specializing in trauma.
There seems to be some bugs related to Apple shipping broken command line tools (again). I've gotten most of my ports built, but I did install an instance of pkgsrc to get the remaining ones until MacPorts gets things sorted out. Clearly not as convenient as Homebrew, but I've always enjoyed being able to tweak compile-time options with MacPorts, so I'm sticking with it.
Back in the day before things like homebrew it was far worse... the days of macports and mod_python to run your Django app are fortunately behind us.