I'm not sure. Historically, dependency generators of this kind
don't
include the architecture information because of the issues related to
determining whether a package is a noarch package or an archful
package (or if it needs to transition from one to the other). It's
somewhat easier to tell on 64-bit (due to path differences), but
harder on 32-bit, because the paths are the same.
I'm also not sure what happens when you just naively add %{?_isa} to a
Provides/Requires set in a noarch package.
I'm not entirely sure that including the arch would be necessary, considering the
repos are already split up based on arch. Seems to me that it would be a little
extra overhead and a fair bit of added complexity, and I don't see any gain.
John.