The reality is often going to be much worse than TSMC's N2 -> A14 "mixed design" 20% density increase marketing spin.

Apparently the N2 -> A14 density increase for logic is 23% (Tom's Hardware), and about 0% for both SRAM and analog.

Both CPUs and GPUs devote considerable space to SRAM (registers & cache), and are 50% or less logic, so for them the density increase will be more like 10% rather than TSMC's 20% marketing number.