Why did Isuzu go from 5.25's in old troopers to 4" in everything made since then it seems really dumb my rodeo has pods behind the rear seats that look like they would fit 6 1/2's and isuzu put 4" was that a cost cutting measure?

94 Rodeo 3+3 lift Red)
95.5 Rodeo 1" Body lift Dana 44' front & rear 4.88 gears 35"s 176,000 miles Optima Yellow top InexAir Co2
front winch bumper custom rear bumper, Hella 500's
2004 Silverado duramax