This is an ancient argument because no one can convince you that you need 3 for your use case. All I can do is say why I like it, and list reasons that probably don't apply to you or you would have switched already.
For example, print and division made more sense to me in 3, judging from friends who taught 2 and said those were always sticky for some students in every class. Intuitive lowers the barrier to entry. (But 2 is probably more intuitive to you because it's second nature to you by now.)
Unicode--when I would test some tiny scripts with Chinese characters or weird ciphers--was pretty easy out of the box in 3.
On systems that only support 2 I find myself slipping in basically a 'from future import all the things.'
These are admittedly mostly cosmetics. But cosmetics matter for noobs like I was, or maybe still am.
I guess 3 also fixed ambiguity in corner cases for error handling? Never came up for me so I don't know much about that one.
You probably just don't have those use cases?
Two people could use distinct subsets of python and neither is using it wrong. Meaning... there could be reasons many of us want 3 that simply don't apply to you. Which sucks, because you get hit with switching costs to help the rest of us.
I think that's the recipe for an endless debate with two reasonable sides.
I will say py2 was already fragmented without 3. PaiMei only ran on... 2.4 maybe? You'd find weird projects that you liked that would then get abandoned. Suddenly you're shimming them all or running four versions. I think 3 woke people up to this as a problem--by making it much harder to patch and way more universal. That made the project more conscious about future and backwards compatibility. Those dividends will only be seen over time. I hope they vest but can't prove how or if they have.
I hope this is helpful... Just know that I'm not saying you're wrong to want to use something that works for you. Switching costs are a real thing, I know it sucks to feel dragged along. But py3 is a lot better for me and others, possibly because we're using the language for different things.