Looking at it from a high level abstract perspective, look at an engine as just an airpump. Air gets pumped in and air gets pumped out. There are 2 ways to pump more air. One, is RPM, the faster the engine turns, the more air it pumps. The other is compression. The higher the compression the more VOLUME of air it pumps.
Here is a good CPU analogy. A CPU's overall speed can be measured in calculations per second. There are 2 ways to achieve that (keeping it simple on purpose). One is the increase frequency (from 1Ghz to 2Ghz) that is equivalent to engine RPM. The other is to increase bandwidth/cores/threading (from doing 1 operation per tick to doing 10 operations per tick) that is equivalent to engine compression ratio.
You're mixing up different concepts. What you are thinking of is that a 2L engine at 10,000 RPM can move the same volume of air as a 4L engine can at 5,000 RPM. Compression ratio is irrelevant in that concept. Consider that both the 2L and 4L engine have identical compression ratios, and the statement that they flow the same air remains true even with double the RPM between them.
Changing compression does not change volume air flow; volume increase at bottom is canceled by the volume increase at the top. Swept volume stays the same, only ratio changes (see fraction math above).
What you meant to compare is RPM and/or displacement vs air flow.
In your analogy, fast clock speed = RPM, number of parallel operations = displacement/cylinders. But compression ratio is something else entirely, a third independent variable, like a die shrink, doing more with less transistors or making the transistors more energy efficient or increasing/decreasing power and heat dissipation, high K dielectric, something along those lines. Note especially that the latter improvements can be applied to *both* fast/narrow CPUs as well as slow/wide CPUs, as can compression ratios be applied to either type of engine, independent of RPM or displacement.
Current evolution of engines is like being at a core count and clock speed limit, and high K dielectric or whatever new gate design or material allows for smaller dies, more transistors, etc. Note that engine displacements and RPMS have held relatively steady over the years as manufacturers reach a brick wall with making cleaner and more powerful engines, but direct injection is like that high K dielectric or something new that allows an increase in compression ratio and higher air/fuel ratio finally to get more power and cleaner emissions and higher MPG without changing RPM or displacement. What about detonation? On a direct injection system, the cylinder only contains air during most of the compression stroke, like a diesel. No fuel to detonate = higher compression, and since fuel is ignited immediately upon injection, it burns controllably AS it's injected over a span of time, rather than the entire PREloaded cylinder going off at once like a bomb.
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