No it is not an illusion. It is discharging through that long PVC through the low bulkhead. There were concerns about the back pressure from the sump being an issue, but truth be told, I have to dial down the gate vale quite a bit to get the level in the skimmer where I want it. So the back pressure is not an issue.
The trick is that the sump level needs to be consistant or else you may have to much to to less water in your skimmer depending how your sump level is.