Yeah Mazda was never great with rustproofing. Like your Mazda 3, this CX-5 isn't a bad car, it's just aging faster than I think it should. Wheel bearings that bad to replace?
It's a 2015. I like the SuperCabs. Enough room that I can fit people if I have to, but if I'm with a group, no one is choosing to take my truck if it means riding back there. Its actually not that cramped. I'm 6'2" and I can sit back there. It's tight, but I fit. The supercrews are nice, I love how spacious the rear is, but I never ride back there. The Supercrews with the 5.5' box are very common. The 5.5' box is just too short for what I need to haul and the Supercrew 6.5 bed has the turning radius of a barge.
They're not a unit bearing design like most FWD cars nowadays. In theory, one could remove the CV axle from the hub, use a slide hammer to pull the hub from the bearing, remove the c-clip and then use the slide hammer again to remove the bearing and then do the reverse to reinstall. I've always had to pull the knuckle from the car and use a press to get the hub out of the bear. And every time the bearing has separated on me. So then you have use a bearing puller or cut the bearing race off the hub. And then use the press again to get the remainder of the bearing out of the knuckle. Just a way bigger pain than it needs to be.
If you're not in the rust belt, maybe it's easier. I just find I go through them way faster than necessary.
As for the truck. Yeah, same here. Didn't need the Super Crew for 90% of the time and found the 5.5' bed too small. The things long enough without going to a Super Crew with 6.5'