There's no desperation here. There's a huge difference between desperation and risk. Desperation would be to keep TruJ at whatever the cost. Actually, 2016 and 2017 were the desperation years when they franchised tagged a mid-level CB and paid him enormous dollars. Remember: TruJ made it clear on numerous occasions that he really wanted to stay with the Rams.
There were other CB FAs on the market and others that could be traded for, and it's a strong year for CBs. But the Rams didn't get a 2nd tier FA, or a rookie: they got an elite guy (a proven guy) for low salary cap number.
Yes, there's risk. But any business decision weighs risk against reward. The Rams feel the reward is greater than the risk. Clearly you and LA feel the opposite. Only time will tell.