"Real hardware" is also an abstract machine. Until you get to the level of each individual transistor, it's hardware abstractions all the way down. Caches, reorder buffers, load and store buffers, instruction decoding are all abstract concepts sitting at a much higher level than the individual transistor.
Those abstractions are there mostly for the purpose of speeding up code execution, but also for enabling hardware designers to think about the machine in terms of real-world concepts and not just as an incomprehensible mind-blowing collection of a few billion transistors.
Those abstractions are there mostly for the purpose of speeding up code execution, but also for enabling hardware designers to think about the machine in terms of real-world concepts and not just as an incomprehensible mind-blowing collection of a few billion transistors.