Regress to the mean. xFP. If he starts to live up to his xFP, then he's "regressing" because "regression to the mean" means he scores an amount of points closer to his expected points, which means he's scoring higher than he had before comparatively because his xFP was so much greater compared to his actual points.
The thing here is the difference between actual points and expected points. You "regress" when, if you have underperformed, you score closer to the expected point total than you have previously.
Say Receiver A scores 8 actual points out 15 xFP for Week 1, 7 actual points out of 17 xFP for Week 2, and 14 actual points out of 15 xFP for Week 3. For FF scoring, we only count 8, 7, and 14 points, right? But Receiver A, if we look at the average receiver when given the situation and whatever factors you're holding constant, was expected to score 47 points. So our Receiver A underperformed an average receiver in history by a total of 18 points.
But even though he underperformed in
every week, the last one, Week 3, is "regressing" because it's showing less of a difference between his actual and expected point total. -7, -10, -1
Important: "Regression to the mean" in fantasy football terms when discussing expected points is usually a term of art when considering cumulative expected points because it's not really a true mean you're regressing to in a mathematical sense, but a decrease in the variance of actual points to expected points from week to week. The baseline is moving and his xFP can change for a variety of reasons, so using a true mean of xFP isn't always a good idea. We assume it will be relatively constant, but there are instances where it isn't.
So, in sum, it means Olave scores more actual points than in previous weeks when compared to his xFP for that week. He is therefore "regressing" but scoring more because he is closer to what you'd expect given his xFP and given his prior underperformance in actual points vs. xFP.
I hope that clears it up. Goggins means Olave will, in the future, score more points than he had previously, which will be "regressing." But even though he is scoring more points, he will be on Goggins's bench because Goggins can't trust him (not due to underperformance in relation to xFP, but due to performance compared to alternatives scoring more actual points in Goggins's WR spot) to score more actual points than Goggins's other WRs score actual points.
eta* I keep editing because of the way the industry uses "regress" and how FF players are supposed to see it.