Is Sapa worth visiting, or has it become too touristy?
Sapa can still be worthwhile, but go for mountain air, walking and a different northern rhythm — not for the idea that it is untouched. If your route already includes Ha Giang, make sure Sapa is adding something, not repeating the same longing for mountains.
Answer
Sapa is a classic case of a place being both over-sold and still useful. The scenery can be beautiful, the cooler air is a relief, and trekking can add texture to a northern trip. But the town and main routes are firmly on the tourist map, so travellers expecting quiet authenticity on demand may be disappointed. The better question is what role Sapa plays. If you want terraces, walking and a softer mountain base, it can fit. If you already have Ha Giang or a slow northern loop, Sapa may become the extra stop that makes the route feel heavy. Give it enough time or skip it cleanly.