Understanding assembly changes how you write high-level C++:

1. You understand why passing structs by const& avoids unnecessary stack copies.
2. You see how compiler vectorization (AVX2) transforms loops with -O3.
3. You understand cache line alignment (alignas(64)) and false sharing across CPU cores.
4. You immediately recognize what compiler-generated boilerplate looks like (VMT thunks, RTTI, exception handling tables).

Everyone who writes C++ should spend at least one month stepping through disassembly in x64dbg/IDA.

Couldn't agree more. Looking at the generated assembly in Compiler Explorer (Godbolt) makes you write significantly faster code.

Assembly demystifies how computers actually execute instructions.