JSON-data import mistakes data type and value for many records. The import process ended successfully: no alert was displayed.
As for instance, here is the JSON fragment taken from the file to be imported:
Here is the related entry once the import process has been done:
Note that some of the fields were changed from a valid number to a "true".
Not all the records are broken, and not clear what is the reason for a so strange behavior.
The JSON file was exported with a MongoDB Compass 1.21.2 on another Windows 10 machine.