When you start backing out limb bolts, the lateral tension immediately begins decreasing. By the time you get them out to the point where there might be a danger of them breaking, the load is too light to be a problem... Or wouldn't be a problem if the bolts were long enough. With the too short bolts they're putting in 'em now, the limb is still under a good bit of tension when you get to the end of the bolt. Prior to about 1990, and they started putting more prebend in the limbs without increasing bolt length, all vert bows could be completely disassembled without a press. Just back out the limb bolts. By the time you got to the end of the bolt, the limbs were completely relaxed and falling out of the limb pockets. And those long old limbs had a lot more potential bolt breaking leverage than the short limbs on today's vert bows or crossbows.

Surely I'm not the only old timer here that remembers that.

Even if your premise were correct, it would be a simple matter to just use larger bolts, like 3/8" or even 1/2", which would take more lateral strain without breaking. Naturally, it would take a modest amount of redesign and reprogramming on the machinery to accomodate longer and/or larger diameter bolts, but heck... Being forced to use a press for such a mundane chore as changing a string is, in my opinion, an idiotic design flaw in the first place.