Please don't delete your Reddit account. It is of minimal impact to Reddit. Keeping a database of users and their posts is far less resourceintensive then actually serving them, Reddit won't care.
It does however screw ppl over when googling questions. We all know that adding site:reddit.com in google search is pretty much a must at this point when searching for solutions to obscure problems. Delete that and a bunch of potentially useful info is lost forever, and Reddit soldiers on without a care in the world.
If you insist upon deleting all your Reddit data, please archive it first, so valuable info isnt lost forever.