Yes. I do this too and wish more people would.
The qualifications, the "what have you been up to?"s -- such mind-numbingly boring conventions. Who wants to go through a "catchup" interview before talking about what's interesting. If that's the price, it's not worth it.
If I think about someone, that's exactly what's on my mind and most interesting. What else would you talk about?
A shared memory, a common friend, perhaps one who's died, their opinion on a movie, a book you're sure they've read, some current event, a funny story they, specifically, might appreciate, etc, etc.
But it's also low-effort and asks the other person to do all the conversational work. For me, personally, if I saw an old friend's number pop up on my phone and magically knew "what have you been up to?" was going to be the first question, I wouldn't answer. Otoh, if I knew the opener was going to be "You're gonna love this story..." I'd be excited to pick up.