We had a 2015 Model S P90D and now have a Model S Plaid. Throughout the time we owned the 2015, we had recurrent screen freezes and blackouts. The car frequently sent collision warning signals from the front left of the car even when driving on open roads with no nearby traffic or obstacles. Every couple of weeks we'd start the car only to get a message that driver assistance and accident avoid features were not available. Sometimes the problem would disappear at the next restart; sometimes it would persist for a couple of day before mysteriously disappearing. The microphone for voice command failed to work as often as it worked. And the voice recognition was endlessly creative in interpreting what I was asking it to do.
And these were the inadvertent problems. There were also the features that Tesla deliberately removed as time passed. Although I had paid $3,000 for the Autopilot option in 2015, which included lane change assistance and operation on properly marked two-lane roads and allowed for choosing a speed more than 5 miles above the speed limit (to avoid getting rear-ended on Florida's public dragways), those features were later removed when Tesla migrated them into FSD. By the time I traded the car this summer, all I had remaining from the $3,000 I had spent was lane keep assist and adaptive cruise control, features included in the price of my 2018 Honda Odyssey that cost 1/3 as much.
The Plaid has had its own share of software quirks, and it was our experience with the earlier Tesla that taught us that paying $10,000 for FSD (that is actually something entirely different from true autonomous driving) was a fool's game, as we were completely at the mercy of what parts of it Tesla might choose to take away at a future date unless we ponied up more money.