IMO the secret ingredient to scaling almost any Python web application, or even implementing it in the first place. It's a shame they had to curtail some features due to lack of funding.
Edit: Apparently they curtailed some features for simplicity as well.
Thank you for the kind words, it's so very appreciated :)
I have merged many features, like broker transports, result backends, etc, and while the initial contribution was great, it ends up being unmaintained with issues that nobody fixes.
If there's any feature that you really want back, chances are the problems with that feature are not super difficult to fix, so please reach out!
Some have the opinion that Celery has (or had) too many features. I know I had to twiddle with a lot of settings in Celery for my unusual use case, but it worked well in the end. There was a long standing bug which ended up being my misunderstanding a certain setting. All that said, I would use Celery again.
Edit: Apparently they curtailed some features for simplicity as well.