I cannot disassemble my 20 year old soccer ball without sacrificing it. Still has lasted 20 years tho.
what does it even mean to "disassemble" a soccer ball?
Exactly. At some point, when the battery gets integrated into the hybrid Display-SoC, what would it even mean to disassemble a smartphone?
I can disassemble my 20 year old Apple Newton, or nearly any other handheld device of similar age. No reason I shouldn't be able to replace parts on my modern phone either!
Sure, but you can't disassemble a tennis ball without destroying it.
The ability to disassemble something has nothing to do with its durability.
No theoretical reason, if manufacturers thought there was a market for the larger devices that repairability would imply.