No, you need to understand how things work.
Many GSync and GSync compatible monitors (Freesync) are not fully certified by nVidia for the full GSync experience. One of the parameters they fail to meet is the presence of flickering whenever the framerate (and consequently the refresh rate) varies quickly and significantly. That’s because these panels are brighter at higher refresh rates, and when the game (any game, not only MSFS) produces stutters and the refresh rate varies quickly between values above and below the minimum VRR supported (typically 48 Hz), you have rapid brightness variations (flickering) due to rapid transitions between 48 and ~100+ Hz.
In previous MSFS builds, the sim was running in a borderless window even when the setting was “Full screen”, and taking into consideration that 99% of the users keep the default GSync setting (VRR only for full screen applications), the issue did not manifest, simply because GSync was NOT working at all for them.
The reason why you won’t see flickering with other games, is simply the fact that they are not as heavy as MSFS and run constantly above the minimum VRR of your monitor.
Now, with the latest MSFS build (and previous ones, provided that the user applied Gsync both for full screen and windowed mode) AND a fully GSync certified monitor, the flickering issue would not manifest.
Flickering is 100% due to the monitor, not to the software.