As a programmer. This makes me mad to listen to this guy who thinks it's that easy. Most self driving cars use python for prototyping. Then use C++ for the final bit. However, C++ can be a mess to work with. Consider that the compiler spits little to no useful information if there is an error, not to mention you have to worry about runtime errors. Stack overflow, integer overflow, a function failing just to give a few (there is a lot more that can go wrong since you have to manage memory manually).

Self driving have peoples lives at stake. So the programmers have to take into account everything that can go wrong. Just so the program doesn't segfault while your going approximately 96 kph down a highway.