I agree it's not as good as F on other airlines, but I've always just assumed it was because reward availability in F on BA is much better than on other airlines (in my limited experience). I'm actually very happy with that compromise - I can't afford to pay cash for F, but I fly a fair bit in Y (around Europe) and Club World (for long haul) and earn a good amount of Avios, which I redeem for F trips (with Amex 2-4-1).

I would much rather a slightly inferior product that I can actually afford to use than a superior one I'll never have the chance to try.

I totally understand those who can afford to pay cash for F might be slightly underwhelmed, I imagine if I was in their position I'd feel that way as well.