The code running on the CPU isn't the only thing the computer is doing in that one second, the X86{,_64} opcodes we could capture aren't necessarily exactly what the CPU is doing, and code being run by extra controllers and processors isn't likely to be accessible to anyone but the manufacturer.
In 1989, we'd've also been looking at code running on a single core with a single-task or cooperative-multitasking OS (for most home computers, anyhow), with simpler hardware that an individual could completely understand, and it would run at a speed where analyzing a second of output wouldn't be completely beyond the pale.
I've analyzed CPU logs from DOS-era programs and NES games. I certainly haven't analyzed a full second of the code's execution; I'm usually focused on understanding some particular set of operations.
In 1989, we'd've also been looking at code running on a single core with a single-task or cooperative-multitasking OS (for most home computers, anyhow), with simpler hardware that an individual could completely understand, and it would run at a speed where analyzing a second of output wouldn't be completely beyond the pale.
I've analyzed CPU logs from DOS-era programs and NES games. I certainly haven't analyzed a full second of the code's execution; I'm usually focused on understanding some particular set of operations.