I must say I have not always been a huge supporter of BA - I have, in my own personal experiences had some rather unpleasant flights.
However, having had a few recent flights I will take it all back - I've found the BA crew to be more than helpful. My colleague and I (travelling on a staff ticket) were given a tour of the aircraft, including the crew rest areas - which are pretty unknown in my airline! The purser in economy also filled a bag with wine, beer, miniatures etc. for us, and managed to get us an upgrade on the following sector. I am aware that this is probably very against company policy, but it made such a difference to have been given that extra special treatment.
Besides all that, the crew were always coming through offering juice and water. I never felt the need to press my call bell for anything. (Not that I would, anyway!) Compared to Qantas, they were superb. With Qantas, I was offered lunch and breakfast - drinks on top. That was all I had on a thirteen hour flight. Very disappointing.
That's not to say I still haven't had the unpleasant experiences, but the same could be said for my airline, and any airline. If I have appeared "anti-BA" in the past, it has not been the case. I am actually quite pro-BA as an airline, but anti- some (minority) BA crews' attitudes towards my own airline and staff. It is the crew who think they are special because they work for BA that cause me annoyance. I agree they are in a large minority, but they are perhaps the most vocal on this message board.
That, I believe, is why you may find a lot of "anti-BA" sentiment. It is always those with the most stringent views who express the firmest opinions.
Bring on the moderates!