I thought Django Admin was cool when I first set it up, but as soon as I hit a few of the issues the parent mentioned, Admin broke or became irrelevant.
It's super weird because Rails is known for convention over configuration and includes default packages for basically everything you might need EXCEPT auth and admin. Meanwhile Django removes a lot of the magic of Rails and lets you do it yourself, except for bundling auth and admin into the core product.
I have found that at least for my users, admin type functionality and views generally require a lot of custom work that is not easily turned into convention. About 4 years ago I stopped using Active Admin completely and just started using Ransack + Kaminari gems on their own. I have been a much happier with the way that pattern has worked out.
In terms of feature and ecosystem surface, there is one area where I think Django is a clear winner: Django Admin. It is a very mature part of the framework and there is a large ecosystem around it. Compared to how useful that is for standing up an MVP SaaS (especially in anything remotely enterprisey), I would find it difficult to consider Rails if I ever envisioned needing admin.
For what it's worth though, I think that Django and Rails are both exceptional choices and in terms of ergonomics, best in class. I wouldn't have complaints about the framework to coming into a project using either one.