I ran into a performance regression when I upgraded from FMS18 to FMS19, and I was kind of hoping FM 20 was faster.
However, in my case the slowdown only happened while using FMS - running FMP only was just as fast as before. My details here: FMS19.6.3 poor performance on M1 mini / Ventura (Edit: fixed link)
I have not yet run these benchmarks under FMS20.