For me nothing is missing. Just the buildings are not "close to their real counterparts" and they are more generic buildings, but they are not missing. MSFS without Photogrammetry is like running our old sims with Photoreal everywhere and buildings autogen. I fly airliners more than VFR but i do not feel that i am missing anything.
Now the photogrammetry that affects performance in MSFS "seems" to come from the photogrammetry that is added from World Updates and not all photogrammetry.
Deleting the photogrammetry from the World Updates and leaving photogrammetry ON from General->Data option improves the performance as it would when you disable Photogrammetry all together. This suggests that something is wrong with World Update PG.
BUT after so many years i am getting too old to spent my time adjusting FS, i disabled all PG and i am a happy man.
PG ON, FENIX A320, KBOS payware: FPS 24
PG ON, PG World Update deleted, FENIX A320, KBOS payware: FPS 41
PG OFF, PG World Update deleted, , FENIX A320, KBOS payware: FPS 41
I can now maintain 30 Locked FPS anywhere with VATSIM heavy traffic.