When you’re carrying a hundred people inside on a weekend trip, what is “reliably”? 99%? five nines? Planes have a much less risky failure mode..
In fact many of the structural 'factors of safety' in airplanes are only 1.5, as opposed to a FOS of 8 in your car.
So again, it's not about just tacking on redundant systems, it's about getting the experience required to understand all the failure modes. The only times planes crash these days is when we encounter a new failure mode. Rocketry will get there as well.
But I'm not sure that throwing extra engines into the scenario will help much. It takes very precise control to land a rocket. Those SuperDraco things are for going up fast, not coming down with sub-meter accuracy.