It describes various suspension problems that may lead to one of the control arms snapping or a suspension link failing. The problem was initially thought to affect Tesla Model S cars built between 2013 and 2017, but it is not unheard of to have Model 3 and Model Y with suspension problems. In many cases, the failure happens at low speed, making it a benign but costly repair. In other cases, it occurred when the vehicle was moving at speed, causing more severe crashes.
For Spithaler81, it happened while driving under 25 mph (40 kph) in a residential area. When the control arm snapped, it felt like the car had a flat tire, and was impossible to control, steering into incoming traffic. After further investigation, he discovered that the control arm was completely broken off. Luckily, he wasn't driving on the highway when it happened, or it would've ended much worse. This bad experience was not enough, though, as the ordeal continued at Tesla Service Center.
Despite the problem being well known, as admitted on the phone, Tesla SC refused to pay for the repairs. They initially wanted to give him a discount because there was a service bulletin (possibly SB-17-31-001, "Replace Front Suspension Lower Fore Links") for the problem, but then backtracked, saying the car was out of warranty. In the end, Spithaler81 was slapped with a $3,600 repair bill, which he gladly paid, but wanted to keep the replaced parts. This didn't go well with the guys at the service center because they put them directly on the back seat, damaging the leather.
The poor treatment Tesla gives its customers is nothing new. Service center experience is among the worst parts of owning a Tesla; few people have anything nice to say about interacting with the technicians. The problem is tolerated by Tesla, which often hides issues with its cars. There were many cases when affected owners were forced to sign NDAs after being offered "goodwill" repairs when those repairs should've been recorded as warranty repairs.
The NHTSA opened an investigation into the whompy wheel problem in November 2020, although things aren't moving fast enough. The agency has received 43 complaints alleging failure of the left or right front suspension fore links in 2015-2017 Model S and 2016-2017 Model X vehicles. No recall has been issued to fix the problem.