I don't know what you're looking at, but all in-model benchmarks support my claim, i.e. for any specific particular model compared to it's next generation you will never see an exponential gain in performance, nor even a doubling of performance, but only incremental gains in performance not yet breaching a 35% increase, which going from the 2018 Mac mini to the 2020 Mac mini comes close to, but it isn't just true of the minis, its true of all models.