Millions of electric cars, thousands of charging stations, thousands of powerwalls, thousands of Starlink satellites and re-usable rockets weren't delivered?

No one delivers 100%, but that's a historically exceptional track record.

Elon predicted in 2013 that Tesla would be shipping 500,000 cars a year by 2020. That was a crazy insane prediction that he delivered on, among many other similar predictions.

Nobody expects all predictions to come true -- professional futurists have a batting rate of about 10%.

I'm talking about stuff people preordered and still didn't got, not on his predictions.

Maybe people should stop preordering then. It's a dumb practice anyway, in any field, not just Teslas.