New answers tagged architecture
The main reason for separating architecture independent files from architecture dependent is so they do not need to be duplicated across architectures. This is something that multi-arch distributions / operating systems (like Debian) do to reduce space usage in their archives.
If you develop some software (e.g. in C++) and want to test it both on 64 bits and 32 bits Linux systems you might install a chroot-ed 32 bits distribution on a 64 bits desktop, and then it could make sense to share the /usr/share But I agree with you, thin clients are not very useful today (much less than 10 or 20 years ago).
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