A person who has been raped is considered in law to be a witness to the crime. There are many examples where the identities of witnesses are not publicly disclosed - for example where they may be at risk of intimidation or assault by the accused or someone acting in their behalf, because they are giving evidence. It has always been my understanding that THIS is why the identities of those testifying in rape and sexual assault cases are kept anonymous. I have never thought it was because of "shame."
In the ideal world, no person who is a victim of crime or serves as a witness in a case would ever feel intimidated by the accused or someone acting on their behalf or fear being assaulted for giving testimony, let alone because they feel ashamed. However, we don't live in that ideal world. Witnesses can be threatened and at risk of harm for taking the stand. Also in our society, where study after study shows that a considerable proportion of people believe victims of rape are at least partly responsible for their assaults and applies a very different standard of "moral" behaviour on men and women, victims are bound to feel ashamed. Society tells them they SHOULD feel ashamed for being raped.
There should be no change in the law allowing those accused of any crime (including rape) to remain anonymous until they are convicted of the crime. There are many, many crimes where the accused can be ostracised and/or where a stigma remains even where the person is acquitted. Examples include terrorism, crimes involving serious injury, disability or death where the alleged was under the influence of drink or drugs (while driving especially,) child neglect or physical abuse or any violent crime where the victim was seen by society to be particularly vulnerable (i.e. an elderly person, a disabled person.) Being accused of crimes even where there is no physical harm to a person can also result in lasting stigma - fraud, deception, arson, etc.
Yes, there can be a stigma attached to being accused of rape or sexual assault, but in my experience, this often depends on the "status" of the accused and the perceived "worth" of the victim. Wealthy and respected men - think football players, senior people in entertainment, etc.) often retain considerable support, even if convicted of rape or sexual assault (think Ched Evans). Likewise, if it can be argued that the victim was complicit because of things like being drunk, having had sex with the person before, wearing skimpy clothing, being a prostitute, etc., there will likely be sympathy and support for the man, who will be portrayed as having been trapped, confused or simply "made an error of judgement."
It was only because the name of an accused sexual offender appeared in a local paper many years ago that a male friend had the courage to go to the police to report having been raped by the man when he was a teenager. If alleged rapists are given anonymity, that will no longer happen. It also gives the impression that there is something specific about rape - that witnesses (read those who have been assaulted) are more prone to lie than in other cases (for which there is no evidence,) or that being accused of rape inherently carries greater risk of intimidation or assault than being accused of any other crime. Again, I don't believe that is the case at all.