This is what I experience:

create a local kpt package with a binary file in it (e.g. a tgz file). A binary file can be any file whose content is not a valid UTF-8 string.
use porchctl rpkg push to push the kpt package into a git repository
when I observe the binary file in git, its contents and usually its size doesn't match with the original file
if I use porchctl rpkg pull for the same package revision I will also get the same corrupted file that I observed in git

This is what I would expect

Either get back the exact same binary file after a "push + pull" round-trip, or get a clear error message that binary files are not supported.