Gatwick is a bit in the middle
Perhaps precisely why BA keeps routes like AMS, FCO etc - to keep both business and leisure travellers flying with them from LGW which will maintain yields (always a problem for BA and the cause of the demise of the dual-hub concept in the first half of the last decade) because of the split between those taking city-breaks and those on business. Useful to bear in mind that many of those on business taking these flights will be living in Surrey/Sussex/Kent; given so many commuters living in these areas there is clearly demand - so they might as well keep such routes.