To be fair, a lot of people right now would willingly pay $5k for the features that are available now, especially if they spend a lot of time on long highway trips.
The price keeps going up, though: if you bought it right now, it wouldn't be $5K, it'd be $10K. It's possible Tesla's driver assistance systems are better than anything else on the market in their current incarnation, but that's getting to be a pretty big ask.
People who bought a 3-year or 5-year lease from 2016 with the $5k full-self driving package probably should feel pissed for wasting money.