Ratings Oddity?

Today I lost to a higher-rated opponent and his rating went up 24 points.

His rating is not provisional, he's played over 480 games.

Before me, he beat another weaker opponent, and his rating went up 23 points. And before that, he beat a weaker opponent and gained 20 points.

What's going on?

Maybe he just started playing after a long time.

@Robaloooo said in #1:
> Today I lost to a higher-rated opponent and his rating went up 23 points.
>
> His rating is not provisional, he's played over 480 games.

He has a rating deviation of 95 which is quite high and due to a long period of inactivity. The rating deviation is not only influenced by the number of games you played in total but also by the amount of games you recently played. If you don't play games for a year - which is what your opponent did - the rating deviation goes up again.

I didn't know that was a thing. What's the rationale behind it?