Nothing last forever. If it's not the running angle then it's ozone, heat, road salt, abrasive sand or dirt, chemicals wearing them down.
I always ask "How long are they supposed to last?" And follow up with "How long did the proposed solution last?" I've yet to see one rip without evidence the rubber wasn't breaking down and crumbling already anyway.
The quality of the rubber and plastic does make a difference in this from what I see since all CV boots eventually split. It happened on our Jetta and those axles are straight and flat from the transaxle to the hubs. You know where they split? At the valleys and peaks of the bellows just like they did on both my IFS trucks.