> This sounds a bit like telling someone, oh, you could've easily started driving an EV, so that once charging stations were actually out there, you'd have been ready...
While car analogies are notoriously bad, it's much more like "I'm going to buy a plug-in hybrid and use gasoline until charging stations are widely available". You can write code that works in Python 2 that takes zero effort to run in Python 3. I (and many others) have been doing this for years. Just look at the number of packages on PyPI that run, unmodified, on 2 and 3.
I try to write compatible code myself too, and the only reason it's "zero effort" to run in Python 3 is that I've already invested said effort when making it compatible. Getting strings and paths and stdio to be cross-compatible and working correctly in both 2 and 3 can be quite painful in my experience. Which was kind of my point with the vehicle analogy. It requires a significant investment that you're ignoring, and lack of enough underlying support to justify it during that time.
While car analogies are notoriously bad, it's much more like "I'm going to buy a plug-in hybrid and use gasoline until charging stations are widely available". You can write code that works in Python 2 that takes zero effort to run in Python 3. I (and many others) have been doing this for years. Just look at the number of packages on PyPI that run, unmodified, on 2 and 3.
[Edit: gas -> gasoline]