Why do some n/a military aircraft show up as a generic icon, and others a F-16?

https://globe.adsbexchange.com/?icao=ae14d7,ae6879

notice one plane is a generic icon shape, and the other, is very specific to a F-16, but the data is missing including the aircraft type?

is this a database thing where the Hex Code has been tied factually to a specific aircraft or is the map just putting them in at random?

@wiedehopf