I feel exactly the same. I had never played a game before that felt so free. I spent so much time just discovering the world, what you could do. The magic system that invited you to break the game mechanics - at a cost. I love how playful it was, with items like the boots of blinding speed.

I don't know if any game can quite capture what I loved about Morrowind, but you might also like Outward, or Kenshi, if you'd like a similar feeling of discovering and surviving in a strange world that wasn't designed around you.