Brentford had a pretty good academy, but after the big clubs pushed through their reforms it meant that even if Brentford produced a superstar they would likely be whipped away for a pittance.

Also the investment they've made in stats based recruitment means that they see that as being their edge over the other clubs, so it makes sense to divert as many funds towards that as possible.

I think being bad at both isn't a viable option in the long run

The owners also own FC Midtjylland in Denmard, they had never won the league before they took over in 2014, and have won it 3 times since.
They still have a highly regarded academy there, so perhaps the different rules in the english system is whats prompted their decision.
Midtjylland I *think* don't have as much of an emphasis as Brentford on playing the pretty stuff, but that could be horses for courses.
that could also have changed in recent years also.
They have also put a lot of effort into set pieces, and get a large proportion of their goals that way.