The reason?
“the brake, park and antilock brake warning lights have a smaller font size than required by federal safety standards. That can make critical safety information hard to read”
The “recall” will be done via Internet with a software update.
Yeah, calling this a “recall” is really misleading. The term recall means the vehicles need to be recalled back to a dealer for a fix. That isn’t what’s happening here.
The beauty of the Tesla software distribution design !!
With the advent of AI and Quantum Computing you’ll see some amazing stuff in future EVs.
You see the same hit pieces every time Tesla does an update. It’s almost as if the legacy media doesn’t like Elon. 
Whats most concerning is how did a vehicle make it out of the factory without being FMVSS compliant and remain on the road for 10+ years before it was discovered.
What would the turnaround time be to fix this on ICE vehicle? Im guessing longer that 1 day.
Some other possibilities: 1. A prior update created the noncompliance. 2. As part of a user-configurable setting, one of several options is noncompliant. 3. Regulations changed such that the systems are no longer compliant.