Question about be quiet! Pure Base 500DX

Yes and no. It depends. With my 3070, the airflow was completely sufficient. Now I have received my long-awaited 6900xt and it produces too much heat for the case. In my opinion, there are unfortunately no fans on the underside.

You should also be aware that the airflow is not as good with a radiator in the front.

So with a medium-sized graphics card and an air-cooled CPU = yes.
Large graphics card or AiO water cooling = rather not

Yes, even high airflow.
It's in the first sentence in the description 🥴