I write database storage engines. Most of the runtime address space is being dynamically paged to storage directly by user space. You can't use mmap() for this. Consequently, objects don't have a fixed address over their lifetime and what a pointer actually points to is not always knowable at compile-time. These are all things that have to be dynamically resolved at runtime with zero copies in every context the memory might be touched. Fairly standard high-performance database stuff. The intrinsic ambiguity about the contents of a memory address create many opportunities to inadvertently create strict aliasing violations.
I've been doing it a long time, so I know the correct incantation for virtually every difficult strict aliasing edge case. Most developers are ignorant of at least some of these incantations because they are surprisingly difficult to lookup, it took me years to figure out some of them. When developers don't know they tend to YOLO it and hope the compiler does the desired thing. Which mostly works in practice, until it doesn't.
Recent versions of C++ have added explicit helper functions, which is a big improvement. Most developers don't know the code incantation required to reliably achieve the same effect as std::start_lifetime_as and they shouldn't have to.
