Now, that the following browser features are implemented by the major vendors:

- Resizable ArrayBuffers (since July 2024) - transfer ArrayBuffer to a fixed length (since March 2024) - Compression Streams (since May 2023)

nothing stands in the way of selecting a file, compressing it with the CompressionStream API, creating an archive and downloading it.

Nothing special per se, but it's another thing, that can now be done using only the browser.