Please try again, there was a server level issue that was leading to a crash on January 9th 2019
NOTE: This issue is only for the scenario where Illustrator 23.0.1 / 23.0.0 started crashing on January 9th 2019
An error occurred while saving the commentStephanie commented
I went through what sounds like the same scenario and was able to "fix" the situation simply by shutting down and restarting my Mac. I'm sure my computer had been running a few days straight when I encountered the Illustrator problem, and actually had to do the same process again a couple weeks later when I was delinquent and left it running too long once again. Same restart-fix worked, and the bug seemed to have gone away erroneously.
Though I never tracked down any real explanation as to where the problem stemmed from, it hasn't reoccurred in a couple months (fingers crossed).