I'm sorry, but given how much high quality software is written in Python 2, examples of high quality software written in Python 3 more easily would do a better job proving the central thesis of the article than pointing out design defects of Python 2 fixed in Python 3. Because at the end of the day, there are still plenty of design defects in Python 3 (or any other language) that a coder might trip over. I mean who is to say that new yield functionality of Python 3 wouldn't lead to hard to understand spaghetti code? Or the new way of handling Unicode isn't worse than the old way? Listing concrete projects that benefitted from being written in Python 3 rather than 2 would be much more convincing.
> I'm sorry, but given how much high quality software is written in Python 2
The reason for that isn't "Python 2 is intrinsically better than Python 3," though. It's the sheer inertia of a language whose last minor version (2.7) was released five years ago and the persistent meme that Python 3 is buggy and unusable, despite clear advantages as noted in the article and the added compatibility of popular Python 2 packages in recent years.
As with hardware, Python 2 will only die when the top packages completely drop support for it, and it wouldn't surprise me if that happens sooner than later. (Django, for example, will be dropping Python 2 support in 2017: https://www.djangoproject.com/weblog/2015/jun/25/roadmap/ )
Why refer to these as two separate languages? Right now, the vast majority of Python's most popular libraries and packages support both 2.7 and 3.4+ with a single code base. We are a Python shop, and we are doing the same with all our new projects as well. There's a little bit of extra awareness you have to have to do certain things (metaclasses, for instance), but the overhead is no more onerous than, say, following well-defined coding conventions.
The latest Python 2 specification is five years old, but new implementations are still being released (PyPy 4: October 29, 2015). Similarly, the latest Common Lisp specification is from the 80s, but there are still several implementations compatible with modern OS's. As long as the language is useful for somebody, it will be kept alive.
As I understood it he was saying the better way to prove Python 3 is good for creating high quality software might be to look at the high quality software already written in Python 2, rather than pointing out flaws in it - since all programming languages will have flaws (including Python 3)..
