Citation needed. Even the devs aren't trying to sell it as much more than a clean up. Very little is actually qualitatively better, and there are some regressions also - for one, last time I looked it was still about 10% slower than Python 2 in most benchmarks.
I'm disturbed at how "citation needed" has become an argument. Since you are also making a claim (that it is not an improvement) don't you have an equal burden to provide citations? Are citations really what will make this argument?
It is also somewhat questionable to ask someone to prove a negative.
This isn't true at all. The negative is also often seen in the form of a null hypothesis. "There's someone in the fridge". "No, there isn't". Here is a case where we can prove a negative. Some negatives by their nature can't be proven, but as a blanket statement it's false.
You yourself mentioned that benchmarks were worse - this is proof of the negative, and you could have cited those benchmarks in your argument.
I think originally Python 3 was a big improvement. But with the back-porting its features to 2.x, the incremental benefit of upgrading has been steadily reduced.
Citation needed. Even the devs aren't trying to sell it as much more than a clean up. Very little is actually qualitatively better, and there are some regressions also - for one, last time I looked it was still about 10% slower than Python 2 in most benchmarks.