Seem to recall license plates are required to be illuminated as well. What's stopping someone from just adding an additional IR light to those enclosures? Couldn't you just slap an additional bright enough IR light in that makes it impossible to even see the plate clearly through cameras?

Personally, if I cared enough to obfuscate my plate info from these devices, I would just taint their data by wrapping my car in a wrap with various different "plates" themed art. I like cars and the exterior has traditionally been treated like art. Tainting data is just as effective at making the core dataset useless as omitting data in the first place.