As far as the conversation in this thread about Rielly not having a good season goes...I'm not overly convinced he didn't (at least, in relation to his usual standard of play). First of all, point production is an overrated way to evaluate defensemen (and even forwards, but especially defensemen), very disproportionate in our perceptions of a player's value over the course of a season. Secondly, Rielly's 2018-19 campaign was an outlier (in terms of production), not the normal. In fact, this 2019-20 season was pretty standard Rielly compared to 2018-19.
I don't think comparing his play this season to the outlier of a year he had last season is just grounds for saying he didn't have a great season. His primary assist rate (0.52 --> 0.48) and ixG (0.27-->0.24) rates at 5v5 were barely dropped, and he was still elite in transition play, one of his biggest assets. However, in 18-19, his shooting percentage ballooned to 8.62% and this year it regressed hard to 2.17%. Combine that with a decrease in PP ice-time with the addition of Tyson Barrie, and a lot more of it coming on the 2nd unit, and his production with the man advantage dropped from 21 points to 7 points.
Extrapolating from his past PP statistics, one can estimate with his old position on PP1, he'd probably have had ~14 PP points, bringing him up to 34 points, a 59 point pace. Give him last year's 5v5 shooting luck, and he'd have 8 goals at 5v5, bringing him up to 40 points, a 70 point pace...which is pretty much the same as his 2018-19 campaign. The point is, 2018-19 was full of good fortune, and 2019-20 was a bit skewed the other way...the real substance of the player is somewhere in the middle, but I don't buy that he was significantly worse this season.
Even Rielly himself
said, “I think there were times last year where I’d shoot the puck and it would hit something and go in, and that’s just the way it was going. And this year it’s not necessarily going that way.”