Don't get me wrong, I have a lot of issues with Tesla regarding a wide range of subjects, but being deceptive about the car's auto driving functionality is not among them.
IMO, they do a very good job of separating the car's current capabilities with ones that will be available "in the future."
As to summon, my wife uses it nearly every day and never complains about it. I've only used it a handful of times, but it has worked flawlessly every time.
I'm recovering from five spine surgeries over the past four years, so I need to be able to swing the door fully wide to be able to get in/out of the car. I've used it a few times (looking for other cars first, so as to not be an inconvenience) to make it possible to swing the doors without worrying about hitting another car. Works great.
Sorry to hear about others having issues.
FWIW, I have the "continuously hold the button to summon" setting turned off. Don't know if that has an affect on usability or not, but if one setting doesn't work, try the other. Couldn't hurt.