At least here in the English Midlands we don't suffer too much from the sort of petty "football fan" type sniping between EMA and BHX that appears to exist not only between BOH and SOU, but between MAN and LPL, and GLA and LPL judging by threads on AA&R.
Airports play to their commercial and geographical strengths, and pre Covid and before the demise of Flybe the two principal South Coast airports did exactly that, with SOU serving primarily the business market, and BOH the leisure markets. Airports are business, not football teams!!