If you're pulling on the eye end of the rope, I believe this is only a 2:1. It looks like a z-rig, but the load and anchor ends are reversed, so you have a 2:1 on the harness at the lower left with a direction change (no mechanical advantage) on the pull line using the pulley on the handled ascender. Please let me know if I'm not looking at it correctly.
No. It is indeed a 3:1 because the puller is the load and is also moving. Many, many, people get that wrong.