As someone who has made the jump to 3 from 2, I wish 2 would die ASAP. It's a pain to maintain backwards compatibility with my various projects and 3 is demonstrably better.
I’m not sure of their reasons but Apple does not ship Python 3 by default on the Mac. If they did, I would switch. For me, it is mostly about being able to depend on default infrastructure and not introduce dependencies for other people; and generally, if Python 2.7 works it is better to let people use the default "python" instead of requiring something more.
What you're saying makes sense in some cases. In most of the use-cases I've encountered I want to run a separate version of Python than the operating system. This allows me to update Python independently to the OS. I was stuck supporting CentOS5, which ships with Python2.4, long after Python2.7 had shipped. Jumping straight to CentOS6 or 7 introduced quite a few variables (not to mention quite a few bugs in the standard library were patched and it was nice to take advantage of that without upgrading the OS).
I feel like the people who think Python 3 has no future and "will always stay on Python 2" are the same kind of people who thought that Windows XP was always going to be the Windows OS to use. Of course, there's still a lot of valid reasons to use Python 2, like having an older codebase, but eventually security updates will stop and I doubt that Guido and other Python core devs will do anything to support Python 2 after that point.
It sucks to have to migrate code from 2 to 3 in some ways, and while the 2to3 code exists, it only goes so far and does miss some things, and if you have to support both, it's a non-trivial change. But Python 3 is the future whether these people like it or not, and many of the newer features like async/await and inline variable typing aren't going to be backported, so while I think it's fine and there are legitimate reasons to stay on Python 2 for now, it's worthy to start migrating in all but the most extreme circumstances.
