Don't think profit has anything to do with it. Bruce got his license in early 1990s and if you want to fly jets/big planes, getting a job is probably the only financially sane way. Unless you're Travolta levels of rich, just imagine how much it would cost to upkeep and maintain a Learjet, let alone a Boeing...
But it does use time, and together with my hypothesis that Dickinson has got a lot more creative freedom in Maiden than in first stint, puts the solo career on the backburner. Yes the albums are now far longer but he got 25+ minutes of his own solo-penned material on the last record, apart from Harris he is the only one with consistent output in last 20 years, Smith took a while and now Gers is a bit to the sides. Dickinson - constant.
Seems to me he is happy the way his professional life is set up and doesn't feel the same initiative he felt in 1990s when he had to prove his name outside Maiden.