Compared to the best dummy halves.
They are all better defenders when looking at missed tackles to made tackles.
That only tells part of the story. Missed tackles (especially in the middle) are often the sign of a defender that comes out of the line. We know De Gois is such a defender, and if it wasn't what Arthur wanted he wouldn't have been retained.
Another important stat is tackles per minute. Defensive workhorses seem underappreciated by the typical fan, who all appear to admit they are required, but seem to think only a couple are needed by a team. In fact plenty if workhorses are needed to defend effectively - the vast majority of your middle pack IMO. I've been happy with our defence this year, and I reckon our attack has been poor due to lack of quick play-the-balls (plus a lack of one or both halves as well as an unskilled fullback) more than any issues at dummy half.
Ennis and Lichaa are better attackers and McCullough has a good kicking game. They are certainly not pedestrian. And a long way ahead of IDG.
I agree they're better than De Gois but they are still very pedestrian. But that's fine - like us, those teams don't require much from dummy half.