Found a possible fix from a tweet:
Guys this worked for me:
Go to this folder location C:\Users\%username%\AppData\Local\Temp and find the Destiny 2 folder and rename it to something else (ie. Destiny 2_backup) as far I can tell it just has log files for when Destiny 2 crashes. After I did this I was able to
im reinstalling atm so cant confirm, if anyone else can it would be appreciated
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