Joe hates Rick because of what happened in Joe's season.
On Survivor 48, Joe went into the final expecting to win. He played the game he wanted to play, and he thought the jury respected his game enough to give him the win. But Kyle won due to his under-the-radar strategic and social gameplay, something Joe does not know how to do and didn't even recognize at the time.
In the early episodes of Survivor 50, I was surprised at how Joe talked about both Kyle and Kamilla. He seemed to think that they wronged him personally by playing the game that they did.
Both Kyle and Kamilla are out of the game now, but Joe is still traumatized by their archetype, and he's taking all of that out on Rick because he's the most obvious "sneaky" player in the game right now.
I think Joe should be worried about more players than just Rick, but like how he couldn't recognize good gameplay on his own season, he can't recognize it on this season either. Rick's way of playing made it obvious to Joe that he was playing a strategic game, so Rick is bearing the full force of Joe's trauma.