Eh? We're locking the version of the dependency, we don't need to look the particular compiled version of it, because they only differ in which architecture they were compiled for. We want 3.2.0 of dep_x on ARM and on x86_64, the last thing we want is running different versions of a dependency in different environments, that way lies madness.
"Some platforms need newer versions" is the default case; don't make your tools fight it.
That said, package managers that do timestamp-based version filtering would be very useful.