The vehicle I owned prior to our 2012 S was a Lexus LS. It was the first production vehicle with "self-parking" - which was pretty impressive at the time.
But...
To get the vehicle to park - it required moving a parking box around on the console display, placing the box on the rear camera image where you wanted the vehicle to go - and then letting it move around to get into that spot. Unfortunately, you could just drag the box to the right spot - you had to use directional controls to shift the box - which took much longer that the time required to do the parking.
So it was a fun feature to demonstrate to guests - but not very practical for actual use.
We've tried using Navigate on AutoPilot when driving highways - and have tended to go back to just lane keeping, since the FSD/AP software doesn't do the lane changes as well as a human driver - yet.
As the software gets more sophisticated through improved Tesla Vision and better rules (based on actual miles driven) - over time, I expect the FSD software to continue to improve - and at some point to be as good as or better than human drivers in typical driving situations.
But as Musk recently admitted - self driving is harder than he expected - and I also expect there will always be situation with our current FSD hardware when human drivers will do better - especially in unusual situations such as poor light conditions, rain/snow, ...
And that's OK - when we purchased FSD for our 2017 and 2018 vehicles - we didn't expect them to really self drive - but to provide much better driver assistance features - and to continue to improve during our ownership - unlike other vehicles that we could have purchased at the time - which would never get improved or new features...