It may or may not related to this MSFS itself, but sometimes when a game is designed to be rendered at full 100% scaling, it looks weird when displayed on a monitor/TV that has a UI upscaling. It can cause something like a “double overscaling” where the game itself automatically scales to your monitor resolution, but thanks to windows UI scaling, it applies the same technique again to the game which overscales it. Resulting in some cropping issues. I don’t see this as an issue in MSFS though, But I have experienced this issue in other games.
The disadvantage to this is that, if the game isn’t designed to be scaled to full resolution, all the UI will be rendered at its original size, so if you don’t have scaling in place, they’re going to look very small when opened in high-resolution display. Again, I don’t see this as an issue in MSFS, but I did experienced this in other games.