Should I send a message being direct or not?

Consider the perspective of a gay man when answering:

In high school, I met a boy I had a bit of a crush on. He was very shy (like, extremely shy) and only talked to one other person, and even then he would just answer what he was asked, apparently. We only had one year together in school because of the pandemic. But I have very specific memories of some of our interactions:

I remember once in PE class he kept walking behind me without saying anything, and it felt like he wanted to stay close or maybe even brush up against me. At the time I was pretty shy too, and I got kind of uncomfortable and just moved away for a good few minutes because I wasn’t really in the mood.

There were a few strange times when he came up to ask if I was okay because I had lightly fallen or something like that, but clearly anyone could see I was fine. There was a rumor that he used to hook up with a lot of girls before we studied together because people said he was gay. I also know that a lot of girls tried with him and didn’t succeed (all of them, actually lol). I know his parents were conservative and all, because I looked at their social media at the time. I understand that he could also just be straight and shy, that’s a possibility too. I remember we did all our school projects together, and I would always find an excuse so we could meet up or so I could “help” more. Which was funny considering we barely talked, even though I felt all that.

We haven’t spoken in many years, but I’ve never been able to forget this story, and I really want to message him. He has a private Instagram account and didn’t follow anyone from our class (almost no one in general), and I managed to get him to follow me back a few years ago, but I never said anything. On his account I didn’t find anything that suggested his sexuality. I also have a phone number, but I’m not sure if it’s still the same.

Would you say something? What exactly would you say? Would you be direct or not?