Any idea why they would use brushed motors? When every gram counts I would think ditching the mechanical commutator would be a no-brainer, but maybe adding another leg to the H-bridge is a bigger penalty?
*A notable example of this is in the world of RC cars, where rock-crawlers only very recently have started switching to brushless motors using field-oriented control to deliver acceptable very-low-speed behavior. Until FOC controllers became available, brushed motors offered much better low-speed handling.
You can get good control of brushed motors with just a couple of transistors. Good brushless control means FOC, which really requires a fairly capable microcontroller in addition to all the power electronics for variable-frequency drive. While brushed motors certainly have limitations, those were quite well understood by the early 2000s (to the point here that assessing whether or not damage had occurred was "just" a question of "have these few transistors suffered from voltage applied in an unintended manner"). Brushless motors involve way more components with way more integration required to make then small. Far more complexity and potential failure modes need to be understood.
I see what you mean. Yes, agreed.
I don't think FOC type controllers were anywhere near common back then either, which is needed to run a brushless motor smoothly.
There is just so much more that can go wrong with a brushless setup, vs brushed where you just apply power and that's it.