Also see my thread on /r/privacy for more information on getting your content removed from Pushshift, and a chance to talk to the head admin of the project (he seems like a reasonable person): https://old.reddit.com/r/privacy/comments/f639pc/psa_pushshiftio_archives_all_of_your_reddit/
I messaged them through modmail to ask that my content be deleted and account blacklisted, to which they agreed, but eight days later my content is still visible and is still being updated. 😠
Update: I messaged the mod who responded to me today about my content not being removed and it does at least appear to no longer publicly accessible (no idea if it is actually gone from their systems or not). The mod said they’re “not sure what happened”.