After the trade deadline, IMO (and I could be mistaken), it seems the only trades are for players thta were claimed and both teams make a trade. After all, if there were interest in the other players, they would have been claimed. However, hypothetical situation: shortly after the trade deadline, team in the playoff race loses a regular due to lengthy injury, but lacks depth at that position. It would be easier to see a list of players that had cleared waivers so they can inquire about trading for a fill-in for the playoff stretch. Teams could list them on the trade block, but that could be cluttered with players listed earlier in the season and would depend on every team updating their trade block. By having a screen you can see player status throughout the league, maybe trades might happen that would not have occurred before, short of owner listing cleared players or owner publicly asking for trades to fill unexpected roster hole.

Not exactly what you're looking for but you can see players' waiver status if you look at Status Info under "View" on the Trade Proposal screen.