I used ActiveAdmin a lot when I started and it always gave me a headache. From what I have seen of Django Admin (admittedly not a lot) it looks very similar?
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.
It really depends on the specific use case. It's possible to arrive at a point where you'd get more mileage out of using something like react-admin and custom API views. But, until you arrive at that point, something like Django Admin or Active Admin can get you quite far.
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.