I love Gatwick, it's been transformed.
I love flying into LHR though. It's a brand that speaks volumes to me, flying into one of the busiest international airports in the world, Concorde was there, the size of the place, to me it was and still is all of those things. It also felt more premium, and less crowded boarding flights!
Separately I think it actually is in a great location. It is on the West side of London is the natural gateway to everything west of there, it has a very densely populated area, close to so much industry, quick to London centre via Heathrow Express and importantly the serious connectivity hub it is. To TrueBlue's point, maybe a bit of snobbery I guess too.
Gatwick has come a long long way, and I've no doubt it will flourish again. Ironically LGW is a victim of LHRs success, meaning airlines such as BA and VS bed to scale back but cannot forego there LHR slots, hence LGW gets the axe..sad days