Goes without saying that have you changed anything or added content to the community folder?
Have a look at this thread…
Especially the stuff in here: https://flightsimulator.zendesk.com/hc/en-us/articles/360015893879-All-versions-Crashing-CTDs-issues-Checklist
I don’t have the Steam version, so I can’t help. I would try different locations and planes though to see if the issue is tied to content but I’m not really sure.