I'm just speculating here but I bet whoever wrote that article has never had an SP howitzer throw a track on him in a mud hole in the middle of winter.
I split my "career" about equally between SP
And Towed Artillery.
NGL I preferred Towed.
(I'm the white guy)
I mean you're going to freeze and you're going to get wet but you're going to freeze just as much on an SP howitzer and towed is much much less maintenance intensive.