Peters has appeared in six games this season, making 14 combined tackles and intercepting two passes.
Young has 13 combined tackles in five games for Baltimore.
The timing of the move is surprising since the Rams placed Aqib Talib on injured reserve with a rib injury, which means Talib is out for at least eight weeks.
In general, Los Angeles is falling short of expectations in 2019. At 3-3, the team is third in the NFC West and a game back of the second wild-card spot.
Perhaps the Rams simply want to shake up a secondary that's allowing 241.3 yards per game and ranks 20th in pass defense DVOA (defense-adjusted value over average), per Football Outsiders. General manager Les Snead might also be clearing the deck for a larger move prior to the Oct. 29 trade deadline.
The trade comes off as a harsh assessment of Peters, who was a Pro Bowler in his first two years and an All-Pro in 2016.
According to Pro Football Reference, Young appeared in more than 50 percent of the Ravens' defensive snaps once in five weeks. The 2018 fourth-round draft pick played a limited role in Baltimore's defense.
Given the cost they paid, Peters is worth the gamble for the Ravens. The 26-year-old is now on his third team since entering the league in 2015, which isn't encouraging. His production speaks for itself, however.
Peters should help a defense that's giving up eighth-most passing yards (269.5 per game) in the NFL.
The Ravens will have the rest of the season to determine whether they want to offer Peters an extension or use the franchise tag on him in the offseason as he plays out the final year of his rookie deal.