I think it does. I took up making necklaces from beads last year, and loved it, both for the creative part and for the meditative part. Also, you occupy your hands and there is an established hand-brain connection (which is why jotting your to-do list down on paper and crossing out works better than using software) and you must be invoking the hand-brain connection when you sew. Unfortunately I stopped making necklaces because beads and supplies were too expensive, but that short experience definitely allows me to vote for the correctness of your hypothesis about sewing/meditation.