Sorry if it's a dumb question, by why would we expect an equal number? Doesn't that assume that we consider ourselves at the centre of our observable universe?
But we observe a bias. Now, that could just be chance — but it's more likely that we've missed something somewhere so our assumption was wrong. One specific possibility is that the universe has an intrinsic spin, which might be because (per the article) we're inside the event horizon of a black hole which is spinning.
Also, yes: we are at the centre of our observable universe.
It seems to have caught on, but one could still doubt its applicability to all phenomena at all scales.