This is an interesting but little known fact.
Originally the term "anti spin rubber" applied only to rubbers that were meant for spin removal such as Butterfly SuperAnti or Toni Hold Anti Topspin (Now Joola) or Butterfly Spin Killer (no longer on ITTF LARC) etc
But nowadays ITTF will classify any smooth rubbers as anti if the manufacturers request it. I am not making this up but found it in some ITTF technical documentation. I will post link later.
So manufacturerers have been exploiting this of late. So nowadays they claim that their anti rubbers have maximum spin "reversal". How could a rubber be called anti it provides spin reversal and nor removal . Good question.
I have indeed seen some rubbers classified as anti rubbers give very good spin reversal but these are really not anti rubbers in the strict sense of the word.
Just a marketing gimmick to sell more rubbers.