Simply put, if you write me, I might write back. I won't post any letters publicly unless 1) You give me permission or 2) You threaten me.
If you've given me permission to post a public answer, I'll still strip the name and return address off.
If you subscribe to the newsletter, you agree to receive emails, about twice monthly. I will never resell or give away your email address.
My newsletter host gives me information about what site you subscribed from, but surprise surprise, it was probably here. It also integrates with and includes FullContact, which is frankly horrifying, and is still less invasive than MailChimp, which acquired TinyLetter. FullContact attempts to determine whether you've used that email address with any other social media account. (Have I recommended ProtonMail yet? Get a ProtonMail and don't connect it to social media. Not for the newsletter so much as for life in general. That's not an affiliate link; FullContact just gives me the creeps.) I won't use this information to friend-request you on other platforms, because that would be creepy. It's worth noting that I don't have access to FullContact outside of the newsletter analytics, so if you want to talk to me and don't want to give up any information but your email address, email me directly. I like getting email.