For example: 1995 Porsche 911 GT2, 1973 Porsche Carrera RS, Alfa Romeo 33 Stradale
Take one of those (stock) to Nordschleife and see how easy and undrealistic that feels. This happens very often, especially when acceerating out of corner - both front wheels lift from the ground for about 2 seconds. Soft rear suspension aso seems to amplify this. It’s some kind of bug, and it’s very annoying. Can’t really handle with steering wheels in the air 
This problem exists in all cars, once a wheel has lifted off the ground the steering is disabled leaving you unable to set the correct steering angle for when you gain traction often resulting in a “tank slapper”.
The steering shouldn’t be disabled when a wheel or 2 is off the ground…
Yes. All cars suffer from this. I drive (the very little time I was able to play this game) mostly heavy sedans RWD and AWD. They all did this. No rear downforce added.
I have witnessed this as well driving rear engined cars.
1973 Porsche 911 Carrera RS 2.7 does this a lot.