This claim is not true.

As someone who drives a Tesla with the FSD beta, the vehicle has been getting progressively better since 2018.

It’s drives smoother and brakes more predictably dive they stopped using the front radar.

This claim is not true.

As someone who owned a 2019 Tesla and who owns a 2023 Tesla, the older car had better autopilot. It was starting to degrade in 2020. The new one is worse. Phantom braking was quite rare in 2019. The very first night I drove home the new car, it phantom braked on a lonely, empty stretch of I-5.

I want the radar back.

FSD stack is disabled on highways. You are using the years old code. Beta v11 when it comes out will enable OP's FSD referenced improvements for highways.

I used to mock my relatives for not wanting to put their kids in a Tesla. But yeah, I'm not subjecting my family to beta software for a critical safety feature, nor should anyone else.

I definitely have some relatives that I would trust less than Tesla to drive with my kids.

In reality, we have Tesla vehicles that sold with other sensors that are now disabled, and those cars are now better to drive with automation enabled than with the extraneous sensors, even simple cruise control is better and phantom braking is actually decreased vs spurious radar returns that existed previously, due to the limitations of low resolution radar. Auto high beams is now better at not blinding oncoming drivers with bright headlights, etc. - issues that happened all the time when other sensors were used previously.

How is your experience the direct opposite of the parent post, given the same change?

Believe it or not, if you spend enough time with a Tesla, you quickly realize that actually detecting things is a solved problem.

The thing they need to improve and are doing so rapidly is actual trajectory policy calculations.

And that’s not going to get better with more sensors seeing the same things it already sees.