It would only be 3664 x 1920 as the two displays are side by side, therefore the horizontal FOV is doubled but the vertical remains the same. You woulnd’t actually want to run a Quest 2 at 3664 x 1920 however as that’s the resolution of the displays and not the headset’s render resolution.
You have to account for the distortion introduced due to the fact you’re viewing the displays through curved fresenl lenses, that mean the centre of the image is slightly futher away, (barrel distortion) and there rendering quite singificanly below its actual resolution.
The proper resolution for the Quest 2 is 5408 x 2736 which gives an undistorted, barrell distortion corrected image. It looks fantastic at that setting, in some games actually better than if I run my Reverb G2 at its native display of 2160 x 2160 per eye. Of course you don’t want to run the G2 at only 2160 x 2160 per eye either but rather a total resolution 6336 x 3092, which looks amazing, but isn’t possible yet in MSFS unfortunately.