John Mueller from Google was asked if you should worry that massive link disavow lists can hurt you negatively and also if you remove the list that it might also hurt you. John said you should not be worried at all, when he was asked how worried should you be, he said "zero."
This is a hard topic to cover because there are two different but similar questions he answered with the same single answer.
The question was posted by Michael Martucci who wrote:
If you have a client with a wild number of domains in their disavow file (think tens of thousands), how worried should they be that:
a) This out of control list is impacting them negatively
b) Removing this list will somehow destroy their website
John Mueller replied on LinkedIn with a one word answer, he wrote, "Zero."
Here is a screenshot of these posts:
This whole thread stems off a post by Cyrus Shepard on disavowing all the links to his website. Of course, this experiment ran over the same time as the Google Search Console link report bug, so that makes it tough.
In any event, these link topics always ruffle feathers in the industry.
Forum discussion at LinkedIn.