I am also experiencing weird CTDs lately. Did not happen for two years and now it starts again. It normally happens after 1 or 2 hours of flight which makes long haul flights more or less impossible. My system can handle the sim quite well with a 5800X3D and 4080 Super with 32GB of RAM.
I already tried to narrow it down but undervolting and GSX Pro do not seem to be responsible so far. It’s a bit tedious as it always takes a long time to switch off a mod or altering the settings and then do the whole trip again. I already removed most liveries from Community folder.
Other than that, I use GAIST and FSLTL.