Apparently the new driver has DX12 enhancements for big performance improvements in previous gen cards as well:
https://www.neowin.net/news/nvidia-52225-whql-driver-has-rtx-4090-support-dx12-improvements-and-more/
Worth a test...
Two things to try. In Windows Disk Cleanup, select and delete the DirectX Shader Cache. And inside the sim, delete any existing rolling cache (if you have it set).
HI Mark - happened to me as well (due to a CTD). Confirmed that deleting the config.json and letting the be recreated on next launched fixed the issue (in case this helps anyone else).
Toggling online functionality allows me to at least hard-select the west coast server (and pings are fine once connected). Must have something to do with the server auto-selection which is having issues here ATM.
Back to the OP - here are some suggestions you can try to get the packages to restart:
All versions - Packages installation and decompressing issues - The download is stuck on small files/packages – Microsoft Flight Simulator Support (zendesk.com)
All versions - Packages installation and decompressing issues - The download seems stuck on "big files" – Microsoft Flight Simulator Support (zendesk.com)
There really is a need to streamline and debug the entire install / update process...