Lack of care, slip ups, and bugs are basically a constant that will always exist. But we can architect systems which are secure even in the face of bugs. Multiple layers of security mean that even the most critical kernel bug in iOS can never extract your faceid data or encryption key because the hardware physically isn’t capable of it. OSs like Qubes utilise multiple VMs so any kernel bugs have limited reach.
When you look at consoles, they have built software that is resistant to outright glitching the CPU.