As stated in the FAQ linked above, those are performance tips, not mandatory settings. The settings chosen are completely up to the discretion of the user based on their personal experience and preferences.
Unfortunately, just as a low-spec PC will struggle to run MSFS at Ultra Graphics settings, with high-fidelity third-party aircraft and high-quality third-party airport scenery, Xbox consoles will also struggle (particularly the Series S with its extremely limited VRAM).
As Xbox users don't have access to the Graphics settings that PC users do, there is a very limited number of ways that performance can be adjusted. The tips listed in that FAQ are some ways that Xbox users can improve their performance if required, based on our experience when testing products.
Mark - Just Flight