The point is solely that everything is visible so it can be downvoted

At which point the abuser will stop doing it, most likely. Which is good. And then they will do something else to obtain a similar level of rewards (circular voting / vote-selling are just examples of such methods that are still likely to be employable under HF21).

As such I think that the benefit brought by the CLRC change is very small. The cons of that part of the EIP outweigh the pros.