The public types emitted for bson.d.ts are wrong:

export declare namespace BSON {
    const ObjectId: typeof bson.ObjectID; // 👈 notice the capital D in ID
    type ObjectId = bson.ObjectId;
    const ObjectID: typeof bson.ObjectID;
    type ObjectID = bson.ObjectID;
    // ...
}

This is really weird since we're importing the right type from the namespace:

We should be able to upgrade to bson@6 by now and this will fix the issue since that has removed ObjectID (capital D) entirely.