It's great to be able to define a DB model, and in a few lines of code have the API endpoint for that DB entity up and running.
When you start getting to complex apps, you may find yourself fighting against the framework somewhat in order to keep your concerns separated, but that's a Hard Problem in general, and so I don't think it's a flaw of the framework itself (though there are a few areas where DRF is opinionated that I think it should not be). If you were using Flask, you'd have more freedom to tweak things when you get to this point, but you'd also have spent 1.5x the dev effort building all of the things that Django/DRF does already.
In short, if you don't know whether you need Django/DRF or Flask, you probably need Django/DRF. Once you have enough experience with Django/DRF to critique that stack's design decisions, you'll be in a position to make good decisions of your own with Flask if Django/DRF doesn't meet your needs.