You don't know that "most of them are very profitable". None of us do, if they were "very profiitable", they'd be getting Club Suite and not staggering to end of life with 8 abreast, 1/2 of 'em rearward facing. They told us LGW short haul was profitable, and then when COVID came, that was retracted!
BA haven't put new long haul metal into LGW since the hub experiment in the mate 90s, it's always going to be hand me downs unless a new CEO decides he/she has a stellar business case for CAPEX.