I searched “MSFS CTD on startup” on google and found many suggestions/guesses (apparently this issue is common), one of which was to run a verification of installed files using the steam interface. I did that and it deleted some kind of “installed” file before even checking file integrity. Upon MSF startup it went directly to “Installation Manager” and is now completely re-installing MSFS (1.22 GB). At my 25mbps download it will take all day. I will try it tomorrow and see what happens. 
P.S. My suspicion is that the original aborted startup left some kind of residual file that is causing the CTD’s, and that the complete re-install will fix the problem. Perhaps I should put a post here that MSFS 2024 should have a “clean up” utility that purges all remaining bits from a CTD so that MSFS does a “cold start”.