He was on the ice for one goal against in the series out of 12, so I'm not sure how much it matters. Rykov isn't the reason CSKA lost the series.
I think Hartley's right that he's soft. For a 6'3 defenseman, he's not physical. Don't agree that he's bad defensively or he's a bad skater. And I'm sure if Hartley's notes were longer, they'd note that he's a good east-west skater. Skating in the simple terms is usually just referring to North-South, where he's probably a little below average. Not that bad though, and he's 6'3. It's really not anything of note actually. And defensively, I think thats just an exaggeration. He's probably about average defensively.
Anyway, I'd expect he'll return to CSKA next year, or sign with another KHL team, and maybe he'll look to return to the NHL in 2-4 years.