Isn't the issue that the system can be abused to ruin innocent people's lives, not that it is sometimes effective.

How about a hypothetical regulation that will allow police to take the possessions of any person because they may be guilty of a crime. Without even reasonable belief they will be charged, as in RICO. Basically a law that allows police to take anybody's possessions any time for no reason. You could use exactly the same argument you are using now to argue for this hypothetical regulation.

Essentially, if no one has any possessions, they can never use them to commit crime. Problem solved, who cares if many innocent people are denied their rights?