You probably see this attitude a lot because of modern C++ features that do make it a lot easier to write safer code. However that is not absolute.

Just the other day I had used std::sort on and std::vector. Pretty simple stuff, figured there can't be a way to screw that up, but my app kept crashing in the sort call because it was trying to write past the end of the array. Turns out if your comparison function doesn't perfectly follow strict weak ordering sort will just blow the bounds of your array without checking.