These phones S20, S20+, & S20 Ultra (I assume same applies to Note 20's) have an in bertween refresh rate of 96 hz; this was already built into these phones, but a guy on XDA made the app so you could go from 60 to 96 to 120, your choice. Maybe this might help you some...??? - - I had installed it for a while, but later removed it. I'm running at 60 hz refresh, w/ WQHD resolution so I can conserve battery. Since I'm not playing games, it's no big deal for me.
The phone has a variable refresh rate, which means it detects what is needed and pumps that out, your testing program may not have been adjusting for this.
I just ran the same test and got 119hz, letting it sit for a moment it went down to 60hz, then used my finger to scroll the page, and it went back to 120Hz, showing how the Adaptive refresh rate is doing it's job.