It’s the same for me, since christmas holidays it became unplayable. Weather service does not load live weater, AI aircraft disappears as soon as it touches down, ATC not talking to me, low FPS < 20 all the time even on small aircrafts without heavy rendering scenery / NPCs, CTD after some time in the air.
It seems like usually the devs do some kind of clean up jobs in the backend to prevent those issues caused by some issues in the software they are not aware of yet, but now with the holidays they did not do anything so it gets worse and worse. My hardware is not somewhere near it’s limits (CPU 50%, GPU 35%) so it has to be something with the software.