Fair question, and the answer is a measurement rather than a preference. A tarball of the fixture is tiny - 7 KB for a thousand empty files, ~150 KB for twenty thousand - so shipping it costs nothing in bytes. It saves nothing in time either: 1000 files take 32.8 s to create with the shell loop and 39.6 s to extract from a tarball on the same phone, because the cost is a per-file round trip into the storage layer rather than the bytes or where they came from. .nomedia, which should have kept the media scanner away, made creation slower still at 46.8 s.
So the useful policies are the ones already in place - reuse the folder that is there, and build the size the question actually needs - and PERFORMANCE.md now records the two negative results so nobody spends an afternoon rediscovering them.
SoftwareApp
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