Looks like the worst "joyride" ever.
O.P. Looks like a legit BMW sanctioned "after service" test run to me. Hard for me to believe that the service tech was doing that for "fun".
As for "flooring" the car, I'll confess that there's not too many days when I don't drive like that. These cars are built for that.
The only thing I find surprising is that that left your dash cam on. Whenever I get my car back from BMW service, the power cord has been pulled out of the dash cam.
