Only too many people don't slow down
And it's a fight to get them stop driving as they approach being legally blind. So people kill themselves and each other in large numbers under similar conditions. Hence the large number of "turn your headlights on during the daytime" sections over here.
The core issue here is, as it has been over and over with Telsa in recent years, in them implementation more than the approach. The car should have warned the driver and kicked out of self drive, if necessary slowing down till they took over. Better camera's may increase the window where the the system can see slightly, but the failure here was in the logic of the system's operation. It failed to judge the cutoff, or anticipate things like fog by using additional information like a weather report or info from other cars, or that it was about to point itself into the sun. I have an app on my phone that does that calculation and plots it into an AR view in real time. Musk is rushing to save his tanking stock price and cutting corners again.
Lidar wouldn't ever let a car safely operate consistently under those conditions, or operate on it's own without other sensors. It might let it operate slightly less unsafely for the brief period it's screaming at the driver to take over or to stop. In either case the software of the system needs to be able to reliably tell when it can't operate safely. Tesla is cutting corners again, which shouldn't be tolerated, but that is a problem with their implementation more than their approach.
Waymo cabs with way more sensors aren't magically immune to these problems either. If anything, they are facing more cases where if one of their sensors see's an anomaly the vehicle stops dead or does something stupid. That said Musk is nuts if he thinks he can make a camera only driverless car work in San Francisco year round.
Lidar, radar and cameras all have different trade offs, but if a heavy fog rolls in, or in smoke, it may only be able to safely operate for a few more seconds. Other techniques can do alot more in these conditions, that have little to do with the existing on vehicle sensors. The car should be operating off an accurate 3d model of the road. It should be getting a feed on oncoming vehicle locations from beyond line of sight. It should be getting accurate information on road and safety conditions in real time.
Instead we face-planted on vehicle to vehicle communications. The car is trying to use a ML model to "read" the road on the fly in most cases, even though the companies are buying high-res road data to use in their model training.
In a saner world, these cars would only be operating on a dedicated right of way until we sort those things out. Instead we are allowing some genuinely terrible managers to push dangerously unsafe implementations onto the streets because they know their gravy train of funding is about to be cut off. Nobody is ready, none of them are safe. Some are safer under certain conditions, but that is a game of rock, paper, scissors over which people are killed or maimed, not over which company is safe and which isn't.
And plenty more snake oil salesmen are lined up promising if you ad just one more sensor(theirs) to every car then all of this will go away. In reality, the most any of them offer is a small incremental improvement, probably with a dozen new edge cases that need to be handled. So mandating any specific tech is a suckers game, but it's an easy one to sell, and profitable. The real engineering test is to force the cars to operate safely under the conditions they can handle. If a supplier comes up with better tech down the road that can operate under harsher conditions, that can be a competitive selling point, but that shouldn't stop a competing solution from being used in the conditions it can operate safely.
And that's the rub. Despite years and billions in investment, neither the radar or lidar companies can offer a system that can operate on their own. So instead they want to make it illegal to sell a car without their tech onboard. They push easily digestible FUD. But one more sensor is just another version of the "one more fix" problem people mentioned, and their are no quick or easy fixes on offer here. So any system needs to be able to operate safely in it's limits and needs to be able to stay in those limits reliably.