From the tech design: https://docs.google.com/document/d/1PE5flrsfWQ3KPmmJMx0pnqGLdqj0OrU6oviZJPP-O6M/edit#heading=h.zfag1nhsyj6k 

The existing Export To Language is not used by the extension users. The evolved syntax of supported languages is not adapted by the BSON transpiler, which generated outdated code. Another limitation of the BSON transpiler is the small subset of supported inputs. Only selecting arrays and objects shows the Export to Language Code Actions (see Tech Debt section).

We will remove the `bson-transpiler` package from the extension in favor of exporting to language using Copilot. We understand that users, who don't have Copilot enabled in VSCode will lose the export functionality completely, but we are ok with that, because close to zero usage of it. Removing the `bson-transpiler` package from the project also reduces the bundle size of the extension.