Well if a team loses a top player this year they only get one pick as opposed to two in previous years. And I think they have to offer the player 13.5 million to even get the one pick. So some of the suckier teams could end up with nothing for their player. So if he is a pending free agent that they have no desire to sign there is no reason to not trade him.
There's always risks/rewards on both sides, but with the Wild Card teams only guaranteed one game from here on out, and not necessarily a home game, I still think the risk is greater for the team that's trying to pick up the guy in the last few months of his contract this season.
We're certainly not going to see the top prospect type deal like we did last season (say, Zach Wheeler for Carlos Beltran) if the team that nabs the star player doesn't get the supplemental pick to replace the talent lost. It's just no longer worth it.