BF insists on being friends on facebook

I am in my early 30s and I used facebook for a good number of years in my youth. Now I have not made a facebook update in more than a decade and I haven't added anyone on facebook in years. I would delete facebook if it wasn't for certain facebook groups and the old memories.

The guy I'm seeing recently asked to add me on Facebook. I declined, explaining that I don't see the value in him browsing posts and photos from my high school and early college years. I told him he could simply ask me anything he wants to know about me instead. Despite this, he has insisted that adding me on Facebook is a "necessary" part of getting to know me. He's since started accusing me of hiding things from him.

Part of me wants to add him just so he can shut up about it. I really have nothing on my Facebook that I truly want to hide (some high school posts are embarrassing but they aren't a big deal). Another part of me is bothered that this guy whom I am giving so much time to wants to get to know me through creeping my old Facebook posts, and I want to stake my ground and stand firm on no. A tiny paranoid part of me wonders if he has sinister intentions, like finding my high school teacher's name, the name of my first pet, etc.

Gaybros what do you think of this situation and how would you handle it? TIA