Indeed it is not a problem in itself, and the reason they include their database IIRC is because they can’t access the FS2020 database using the SDK. In other words, when you’ll have a dozen aircraft each one having its own local database, this will be a dozen set of files to keep in sync and update too.
There remain a problem though: because the WASM sandboxed code is only given the permission to accessing a local sandboxed folder with write access just for this WASM sandboxed code, this further limits one of the strength of any other simulator: mixing add-ons.