I was a regular flyer out of BHX and regularly flew from there with the likes of KLM, AF, Lufty, SAS & Swiss with the one time I flew long-haul to/from HKG utilsing Swiss, fantastic service, just a one hour connection each way in ZRH, I actually got 4 engines long-haul ZRH/HKG/ZRH, and I'd like to bet that I might have been just one of a handful of pax travelling BHX/HKG that day, hardly a long-haul aircraft load.
BHX is particularly great for all the feeder services via AMS, CDG, CPH, DUS, FRA, MUC, ZRH etc., there might be 80 pax on an aircraft, 4 of each to 20 different ultimate destinations, it simply isn't going to happen to, let's say, round-up some 250 pax to fill an A350 to just one Asian, African or down-under destination, unless that destination is particularly targeted at the population of the west midlands.
As it is, eastbound, one can fly to pretty much wherever one wants from BHX via one of the close-continental hubs, it worked fine for me as it clearly does for so many others also.
And I'm curious to learn who the first two British intercontinental airlines are that aren't connected to N. America when Virgin Atlantic is 49% American owned and BA is 45% (ish) Spanish owned!