Foreseen it was.

And in a way, those old 8-bit home computers also worked like a single integrated 'super-chip', because the whole system was driven by a single clock and entirely 'hard realtime', while modern computers are much more asynchronous (and I guess this asynchronous design is what enabled most performance improvements that go beyond pure transistor count scaling).

https://codeberg.org/linker3000/Z80-Board

The Z80 could even refresh the RAM by itself. It was not like the 8080 which required two support chips only to function.

Of course, the 8008's origins (along with the completely unrelated 4004) were outside of Intel. They were hired to design custom ICs. The 8008's architecture was dictated by a CTC terminal. While Intel designed the 4004, it was only intended to be used in calculators. Intel, and its engineers, probably put relatively little thought into microprocessor architecture until the 8080.

In general, the reason why modern CPUs are so complex is because the gap in performance between CPU and memory has grown massively over time.

In the old days, something like a 6502 was running nearly synchronously with RAM.

That gap has grown massively over time; a modern CPU is orders of magnitude faster than RAM. So they have to jump through a lot of loops to avoid simply idling 99.99% of the time while they wait for some new data or instructions from RAM. On-CPU cache memory is one answer. Branch prediction and speculative execution are others. As you may imagine, speculatively executing code based on branch prediction is very complex because you must roll back any side effects from that execution if your prediction turns out wrong.

Example:

   # assume `i` is a value stored in main memory
   if i == 42
      j += 1
      k -= 1 
      l = 666
   else
      z = 123
      q = 5879873

That's why we can't just take an R2000 and scale it up to 3ghz. I mean, we could, but it wouldn't work very well unless we also had low-latency 3ghz main memory to pair with it.

Acorn co-founder Hermann Hauser famously joked that he gave the original ARM microchip design team two distinct advantages: no time and no resources. With no money for a large crew or complex hardware, the tiny core team had to keep the processor design exceptionally simple, which ultimately birthed the revolutionary RISC architecture.

It also had to run in simulation on a BBC micro… Probably with a second processor via the Tube interface, but still.

https://www.righto.com/2015/12/reverse-engineering-arm1-ance...