Yeah I know what you mean, I have my PC for that, but some do use them for gaming. The Note 10+ has a Snapdragon 855 or Exynos 9825 so if you do a comparison you will probably find the differences there but the Exynos 990 is an upgrade over the 9825, obviously the Note 20 ultra in some areas get the improved snapdragon 865+ and we in Europe and some others get the Exynos 990.
Some reviewers have said in initial tests that the Exynos version of the Note 20 Ultra tends to get a bit toasty under heavy workloads, but until we actually get the released retail version then we won't get a true idea on this. Review software is not always the released version. I am using a Huawei Mate Xs folding phone at the minute for review purposes and it also has different software to what will get released with the phone.
So in a nutshell the Exynos version of the Note 20 ultra will throttle back more under intense workloads and use more battery than the snapdragon 865+ version.