The only thing I really wish for is an ecosystem "what's now" guide, it would list things such as where the community has moved for common libraries. Off the top of my head it would have covered things like nose to pytest and such. Obvious problem being I just can't imagine how you'd get buy-in to make such a thing work, especially without it getting overrun with grifters.
However, taking "Command-line Applications"¹ as an example it lists six alternatives. I think in the version I'd like to see a good few of them would disappear. For example, I'll presume plac/fire/cement aren't in common use given that only two are packaged in Debian and the two that are don't have reverse dependencies. Cliff looks largely uninteresting too, as outside of OpenStack nothing seems to use it.
I think my ideal implementation would probe recent releases of popular packages for dependencies to see what the community has settled on or moved to. I also suspect this comment that somewhat moves the goalposts also points to the difficulties of maintaining such a document.
That said, when I started out using Python professionally, I got a lot of mileage out of this guide.
And btw, such Wiki exists, even officially: https://wiki.python.org/moin/FrontPage
Although, as you might expect, it is a mixture of outdated, more recent, messy, detailed, lists or guides and everything.
What are the current common libraries also doesn't really have a simple answer. Maybe this should be auto-generated based on Google or GitHub trends.
I followed the Python and PSF community very closely for about 12 years through 2018. I haven't kept up for personal reasons. I suspect they are uncomfortable with doing this because they don't want to feel like they are picking winners. Whatever they list will be "blessed" no matter how many disclaimers are attached. In a way, I observe a similar problem impacting how they've approached ecosystem problems like packaging. There is a clear issue and a central authority was needed to sort it out and that never emerged when it was originally required.
Right now PyPI highlights some trends (https://pypi.org), but there is more they could do. Python success stories at https://www.python.org/success-stories/ could probably be evolved to highlight some of the libraries and tools which get serious usage. Anything that's autogenerated from other sources probably has value, but would only be something that would be compatible if it's detached from python.org. Expanding PyPI trend information would be more compatible with python.org.
There are some cases where it can be nice, but often it feels like a somewhat unnatural bolt-on to the language. I guess OO isn't that widely used in JS anyway.
Stuff like nullish coalescing and spread operators however... those things are great - they can save a lot of code.
The only thing I can think of that I had to really read up on was string handling. Everything else I could just google as I came across it. And even after 6 or 7 years, it all comes back really quickly.
Packaging stuff... weren't we using virtualenv 6 or 7 years ago? And even that - it's hardly difficult to get working with.
This reveals something important that is easy to overlook: while you’re actively working in an ecosystem, you may hear about new things that come along, but if you spend some time away, things may well happen that you didn’t hear about, and so in some cases beginners may even surpass you in current idioms. It’s worthwhile, in such cases, at least skimming over some materials and especially the release notes since you were last an expert—if I were going back to working with Python/Django extensively, I’d read at the very least the headings of the release notes for Python 3.6–3.10 and Django 1.8–.