Did you read this anywhere in particular? Looking to try and learn more. Because it's always been said aimara are the only one found in rapids. And videos of documentaries etc shows aimara do deal with high current areas in the wild. Or you can simply watch fishing videos of them and see their is definitely current in places they're caught. I've also seen aimara keepers report aimara tend to swim in front of current quite often when provided.
However if you are saying they do not need current I agree, it is not a necessity, but something to add to try and increase activity, metabolism, and growth possibly. It also as stated pushes debris around which can be beneficial to net it out or let the filter handle it. Don't go overboard with current but add some imo.