I have driven the X1 and various other BMWs. The X1 is indeed horrible, and there is a reason:
For handling / lateral dynamics: The X1 is derived from essentially a MINI platform which is FWD-based (transverse engine), compared to the rest of the BMW lineup which is RWD-based (longitudinal engine).
For power / longitudinal dynamics: If GP happened to be driving a 3-cylinder, then of course the turbo lag would be high. OTOH, the 4-cylinder B48 is a venerable engine with negligible lag (again used all across the BMW lineup).
For handling / lateral dynamics: The X1 is derived from essentially a MINI platform which is FWD-based (transverse engine), compared to the rest of the BMW lineup which is RWD-based (longitudinal engine).
For power / longitudinal dynamics: If GP happened to be driving a 3-cylinder, then of course the turbo lag would be high. OTOH, the 4-cylinder B48 is a venerable engine with negligible lag (again used all across the BMW lineup).