My LDR partner not adding me on social media

I’ve been in a long-distance relationship for over 4 months now.

We talk almost constantly, share our locations most of the time, and overall he treats me really well. He even sends me gifts despite the distance and the fact that we live in different countries.

What confuses me is that he refuses to add me on social media at all, and the reasons he gives never feel convincing.

Sometimes it feels like he wants to keep appearing single in front of his friends or the people around him.

Am I overthinking this, or is this actually unusual?