Last year, Apple made a surprising move in repairability: it redesigned the iPhone 14 back glass to be easier to repair. But those changes didn't make it to the Pro models, leaving those much more costly to fix. That changes with the iPhone 15 Pro, which is now much less expensive to fix by Apple's estimates.
In the past, Apple used a permanent adhesive on the iPhone's back glass that required temperatures so high that it was easier to use lasers to repair broken glass backs. If you wanted Apple to fix your phone and didn't have AppleCare+, replacing the back glass on an iPhone 14 Pro Max would set you back $550. You could just as easily buy an iPhone SE for nearly the same price.
On the other hand, the standard iPhone 14 model changed the chassis, enabling easier back glass repairs. When iFixit took the phone apart, it said the new layout resembled repairing many glass Android phones. You can take the back off with heat and even get to the battery to swap that out. (That said, iFixit just lowered its iPhone 14 score thanks to parts pairing.)
When Apple announced the iPhone 15, it noted that the Pro models now featured a change to make repairing the back glass easier. We won't know if the changes are identical to the 14 series until someone can take one apart, but it's safe to assume that's the case.
Those changes obviously made a difference: whereas Apple estimates replacing an iPhone 12 Pro, 13 Pro, or 14 Pro's back glass will set you back $449, the 15 Pro will only cost $169. That's a significant savings. And if you spent $199 for AppleCare+, that same repair will only cost $29.
Unfortunately, the same good news doesn't apply to the Apple Watch. Repair estimates for the latest model increased over last year's pricing by $20.