I have an assortment of Django and flask-based websites and Django still works fine for new projects from my perspective, with the normal caveat that it really depends on what you want to do with it. If i had to redo some of my projects I'd probably use the Django rest framework more heavily as I ended up duplicating a lot of that functionality writing Ajax endpoints way back in the day, but I've not encountered issues where Django is the bottleneck in the system. Usually the bottleneck is a poorly optimised database index or something, which Django handles fine to a point.

however, since I've ended up utilizing SQLalchemy and Pandas in a lot of my projects I have since tended to use Flask+SQLalchemy a lot more so my old fuzzy brain doesn't have to try and remember the variations between two different ORM syntaxes.