There is no way that training people not to worry is making us all safer. I don't even like how new cars have this thing where they will automatically hold the brake once stopped even if you let go. There is no way it's a net good to train people that running cars just stay where you put them like an inert object does.
The result for me has been pretty predictable, I'm getting a kind of corrective feedback so I drive in a way that prevents that feedback. The practical result is that imo I'm a better driver, I'm more aware of my lapses in attention, my tendency to overcorrect to the right, and so on.
I'm yet to experience a downside, this isn't like using "Autopilot" or some other situation where a machine is taking over for me. I don't see why our skills or caution would be lessened by exposure to realtime feedback.
Cars have had that feature ("hill hold assist") for 20+ years now. Even longer for high-end models. There can't be all that many vehicles left on the road that don't have it.
Besides, you could make such an argument for any safety feature: "I don't like how new cars have ABS brakes. We shouldn't be training people that you can just slam on the brakes on a slippery surface and expect the wheels to not lock up..."
... "I don't like how new cars have seatbelts. We shouldn't train people that they can just crash into things and not have their face go through the windshield"...