The reasoning here is quite simple.
His value was at its absolute peak entering the All-Star break. He had yet to blow a save and had put together an absolutely dominant first half with stellar peripherals across the board.
There was nowhere for him to go except for down.
Allowing a home run to Joey Gallo in the All-Star Game and blowing his first save of the season in the team’s first game of the second half against the Milwaukee Brewers is by no means going to scare off interested parties.