Watch cases are relatively huge for what needs to be inside them. You can see the difference between an entire smartphone and a simple time keeping device, right?
They also don’t have the long aspect ratio of phones (bending moment).
This doesn’t compare to phones at all. It’s like trying to compare your TI-83 calculator to a MacBook Pro
Now go look up why they stopped riveting ships in the 40's and went to welding, there are no modern riveted ships. Even with the rivets they were forged not pressed, nothing like a screw.
Cheap aluminum boats are still riveted, welding preferred for obvious reasons. I have an old riveted aluminum John boat and is leaks through the rivets and seams...
I think you may need to think out your entire post before typing such contradictions.
Riveted hulls worked for hundreds of years and well maintained they can last forever. Just bacause welding makes it cheaper to maintain in the long run does not detract from the fact that riveted hulls are very performant, which is why they were used everywhere that needed not only waterproofing but pressure containment too.
They also don’t have the long aspect ratio of phones (bending moment).
This doesn’t compare to phones at all. It’s like trying to compare your TI-83 calculator to a MacBook Pro