I don't agree this is reinvent the wheel.
Maybe Slack is reinventing the wheel.
Reinvent the wheel, from the Cambridge dictionary:
to waste time trying to create something that someone else has already created
We are having a good experience with chat support on telegram group.
There is already a long running Brazilian group where we have a great experience, and recently we opened a World group, for support in English.
We will probably create a Telegram group for Web3py too.
A good chat sometimes is faster and we can communicate other kind of subjects related to web2py too.
It has its advantages but also disadvantages.
For example, it is not good for indexing things on topics for later search.
For that, a typical mailing list is still better.
Also, slack seems to have some limitations on free accounts.
I don't oppose to creating a slack account, but I oppose not creating also a typical forum.