This isn't a stupid question, it's an important one and it's not a simple thing.
It all depends on your body type, what kind of gun you carry and the level of concealment you are trying to maintain. For sure barrel length and belt height also matter but I feel if barrel length is the problem then maybe that's not a good gun to carry. If belt height is the problem, the 90s called and they want their horrible fashion trends back.
I like to have enough grip above the belt to achieve a complete master grip, but not so much that the gun wants to tip away from my body. Running a slight cant makes this easier. With anything G19 or smaller this works for me and I don't have pubic bone interference. This works great for a semi-permissive environment such as where you have a permit or it's a state that has constitutional carry and there are no signs saying no guns allowed.
For deep concealment, short of a true pocket gun like a LCP, the grip has to be buried behind the belt which makes pubic bone interference much more likely.