> How would a smaller shared object lead to faster startup? The kernel isn't loading pages to memory unless they're actually used.

IDK on linux but on windows opening a 600mb exe (e.g. release with debug info) and a 15mb one (same but stripped) have a VERY OBVIOUS startup time difference. I assume the OS is scanning the whole binary through some antivirus for instance, and I'd assume the same to be true for DLLs used by the app, so all these kernel loading pages optimizations go through the trash.