I think that the most egregious issues are quite rare. Some panel-gap type issues maybe less so. Yes, we waited two years after placing our reservations, but we knew that the target date was years away, and we knew (or most of us did) that Tesla has had production delays with all its new models. It's common wisdom that there's always risk in buying the first model year of a new car. I bought my Prius in January of 2004, against the advice to wait a year, and never had any trouble, but Toyota is a long-established car maker with a history of extremely high reliability. And I didn't want to wait to enjoy that car, which, in 2004, was really cutting technology.
Similarly, I knew when I bought my Model 3 that I was taking a chance, in order to get this car a year sooner. But the advice is still sound: If the risk is too great for you, you should wait until the quality reaches a level you are comfortable with. I decided the risk was worth it because as bad as some of the reports are, they affect a very small percentage of the cars. But that was just me.
It's disappointing that it's taking Tesla so long to get its QC up to snuff, but I think they're working hard on it. And I think that people who cannot afford the risk, or don't want to take the risk, should definitely wait. Life's full of trade-offs.
My car just arrived a few days ago, and it's a 5xxx. I'm surprised if there are 7xxx or even 8xxx out there yet.