There are lots of threads on this and it's getting a little boring now to be honest.
BA will have to up their game at some point, but for various reasons already mentioned here and on the countless other threads, they're not in a rush to do so. They're clearly thinking about their options however, as evidenced by private presentations given to key customers earlier this year. Some images possibly given at these presentations were leaked to someone I know earlier this year - basically a BA styled Cirrus seat.
Is it the 'best' (whatever that means) thing to do? Maybe not, but it's proven (and therefore safe) to be profitable and has no signs of changing in the short term.