What about parsing that XML upfront, serialising to some binary format (e.g. CBOR, maybe with nlohmann's JSON library, or Cap'n Proto) and shipping the binary file?
Would be cool if we could that, but as things stand, enough various people want to occasionally look at these files, in environments where they can't just install specialized tooling and are using notepad.exe (or Notepad++ if already available), that we keep it text.
I like binary formats, but we can't afford the increased complexity around supporting a custom binary format, so I'm not pushing for changes here.
I did investigate replacing our pile of XML files with an SQLite database, which would give us fast and efficient format, and allow to use existing SQLite database viewers, or hit the file with trivial scripts, so we'd have no complexity supporting a dedicated tool. However, the data model we use would need such a large overhaul (and related retraining) that we tabled this proposal for now.