FWIW, this is what I have been told about drone brood:
Drone cells get in the way of cells that could be used by the hive for workers.
Drones consume hive resources (honey, pollen, space) that couple be used by productive workers.
Removing drone cells can be one part of IPM to control varroa. Apparently (someone correct me if I have misunderstood this point), varroa mites preferentially infest drone brood as it matches up most closely to the mite lifecycle.
Using frames with foundation ‘should’ reduce the amount of drone brood you get, because the foundation is already imprinted with cells sized too small for drones. (In practice, I just end up getting drone brood on the bottoms of my frames, where it is easier to scrap off with the rest of the burr comb.)
I do not attempt to remove every single drone cell. Just the clumps. I figure the bees will just try to make more if I take them all, just to be perverse. (Yes, I personify my ladies, don’t judge.) Frames with foundation make this easier for me, as I don’t risk knocking all the comb off the frame when I cut out just a part.
It doesn’t matter if the wax you save for rendering has brood in it. Just freeze it all in a ziplock baggie until you are ready to render, you are probably going to strain your wax through a couple layers of cheesecloth anyway to remove brood, bee parts, pollen, and other clumps and debris anyway…
Disclaimer: New beekeeper. Feel free to slap down or correct as needed. Still learning here too.