Funny you say that, these startups actually wanted me to be referred to as a cofounder even though I wasn't. They actually leveraged that title to make me sacrifice salary and work much harder than I should have (i.e. many all-nighters). When I found out funding was running out and I was only being paid enough to cover rent I had to leave.
The don't actually delete your posts, they mark them as deleted. If the government requests your data they get to see everything, even those posts you decided to delete.