Smaller, faster, better

A good metric is cost / transistor per processor speed.
Transistors get cheaper and cheaper and the speed increases.
Click through some of the other charts there. Microprocessor clock speed over time. You might find them interesting.
Different technologies like: (GaAs) gallium arsenide, (SoS) Silicon on sapphire , (SiC) silicon carbide have similar shaped curves but are offset up or down. Each technology offers different advantages: high temperature, high speed, low power, radiation hardness etc.
You decide the specifications you need and then look for the best technology at an affordable price.
Magical stuff is out there.