“Compared with the latest 10-core PC laptop chip, the CPU in M2 provides nearly twice the performance at the same power level.”
The real gain over M1 is 18 percent on the CPU, which is a normal year, not a breakthrough. The big multipliers come from comparing against Intel laptops at power levels Apple picked. The footnotes say Apple ran its own tests on preproduction machines. The chip is good. The chart is marketing.