Do you believe they actually delete it? I don't.
I deleted my account with Digital Ocean years ago, because I use NoScript and every time I went to a new page at DO, it required me to enable more 3rd-party domains. I switched to Vultr.com because they only use their domain for their web pages.
Recently I received an email from DO that my acct information may have been accessed by some hack. I replied to that email, requesting that they delete everything on their systems relating to me. They said I had to sign in and purge my account. I already did this, when I switched to Vultr.com. But I tried anyway. It wouldn't let me sign in (Duh! I already deleted the account), so won't let me purge my info. When I explained that DO would have to delete it, they never replied. They obviously still have my info or they couldn't have emailed me.
My level of trust that a company has actually deleted everything they say they are deleting is about zero. If it's to their advantage to keep it, they will.