Very General Non-Specific Diagnostic Process to Identify GTA V Issue Location:
Rename the 'scripts' folder to something else ('scripts - Backup' etc) & test in-game.
If renaming the 'scripts' folder fixes it, remove scripts one by one until you find which one or which combination of scripts is causing it.
Rename your 'mods' folder to something else ('mods - Backup' etc).
Create a new folder called 'mods' to replace your old one.
Test the game using just an empty 'mods' folder at this stage, to make sure it isn't purely just a OpenIV .asi/root folder script etc related issue.
If you still have the issue with an empty/renamed 'mods' folder then:
Check all your root folder scripts are up-to-date & update those that are not.
Test remove root folder scripts one by one, testing in-game after each removal.
If it happens after a new update, wait for stuff like Scripthook etc to be updated.
As long as an empty 'mods' folder works, then start reintroducing '.rpf' archives & folder structures one at a time, moving them from your renamed 'mods - Backup' etc folder to the new 'mods' folder, testing in-game after each change.
The order you do it in doesn't really matter, just keep track of the last change you made.
If a reintroduced folder structure (like the 'dlcpacks' one) seems to cause the issue, remove it back to the 'mods - Backup' & either use the same process of manually reintroducing one dlc at a time to find out which one is causing it, or remove/reintroduce 'dlclist.xml' entries to accomplish the same, if you prefer that.
I think I've remembered all the vital parts .
The beauty of using GTA V & a 'mods' folder is that it's modular nature allows you to move any folder stucture or '.rpf' archive to another folder location on the same hard drive very quickly & without using up any additional hdd space.
Once that is done, the game when loaded will fall back to using the vanilla counterpart in the main game folder instead, allowing you to diagnose very quickly & easily whether there is an issue in that folder structure/'.rpf' archive.