The question, of course, is should such a pill be used? And the answer, really, is why not? It's no more wrong to try to suppress one's memories (or at least the emotional reactions associated with them, which is what's actually at stake here) chemically (ceteris paribus) than it is to suppress them psychologically (ceteris paribus) or to try to come to terms with them through psychotherapy (ceteris paribus). Basically, as with many moral decisions, it's contextual. How badly are the memories screwing up one's life? Is anything less invasive, and less potentially risky, available and effective? If the answers are "very" and "no", then I don't see any reason why one shouldn't take the pill -- and, indeed, I can see a few reasons for it.
These, however, are very stupid reasons against it:
Would you be a worse person if you didn't remember the remorse you felt over doing wrong? How would people learn from mistakes, including in relationships, if they couldn't remember how they felt?The first is stupid because "understanding mistakes", understood in any sensible way, isn't dependent on emotions. I can very well know what wrong (or right) I did, even years later, after any emotional connection has been severed. Claiming otherwise is really closeted emotivism. The same sort of thing applies to empathy: empathy is a capacity of imagination and understanding, not an emotional capacity. (I think the writer may have confused it with sympathy, which is indeed a feeling. However, claiming that lacking sympathy is a bad thing seems to condemn naturally unsympathetic people and people who simply fail to have a particular emotional reaction in particular circumstances. Given that emotional reactions are not voluntarily-controlled, this makes little moral sense -- after all, "ought" must imply "can", hence "cannot" implies "ought not" (or, really, "not ought").)
Empathy might even be at risk: If you couldn't recall, for example, the pain of being fired, would you be able to put yourself in the place of a friend who had lost her job — much less the plights of strangers covered in the news?