This has been going on for a month or so now.
I have a lot of USB peripherals and a lot of different profiles.
It always takes a long time to load, and sometimes when I make a change in one of the setups it freezes the sim and I have to force quit to get the sim back, sometimes it is then OK, other times I have to restart the computer.
I am on latest version as of Jan 11 2022. Store version. I do run X-box app in the background full time.
Problem solved.
I use the Bravo Throttle Q and if you leave one of the buttons selected by pushed down on the axis levers to the bottom, like to put prop in Beta or to cut fuel on the condition lever, then the sim will not be able to save or even do anything at all, it just is frozen.
Move the lever back up and everything works like normal.
I only ran into this when I was trying to set up the Kodiak prop etc levers using the space below the detent.