As of 1.16 we have no way of breaking bedrock. Breaking bedrock is a bug, but it is like quaziconnectivity(which also needs to be added) in that it is balanced and useful. If we had this we could access the nether roof to build farms up there(if the build limit is fixed that is). I suggest making the dragon egg technique possible  where you power a piston in lazy chunks that drops an egg on the bedrock because that adds functional use to the egg and makes breaking bedrock a late game thing.