I get exactly what you mean, but whats happened (especially with Powerplay and its use of the BGS - which is FD legitimising BGS play since its such an important factor in defence via lowering triggers) is exactly that: they are playing the BGS. For a Powerplay group its more about maintaining control over territory far far greater than PMF backed factions ever get to, and doing it as efficiently as possible. I expect the largest PMFs would behave in a similar way, and that what you describe holds true really for small to medium sized groups in the BGS (if that sounds condescending its not meant to be- its just at the larger end of the scale for the BGS and Powerplay you are dealing with multiple PMFs, factions, powers each and every day with more and more added all the time).
FD themselves seem confused too, since the 'black box' of 2015 was opened up and devs have told us INF values of actions, what causes what, and so on ever since. More and more UI feedback as been added over time, as well as making us aware of things like expansions and retreats. If FD wanted the BGS to remain in the background, surely they'd have kept a lid on the black box?