I disagree. Only actually forcing a defendant to testify counts. Whether in a particular case standing silent should be considered evidence of guilt should depend upon the circumstances. If a defendant has been proven to have been present at the scene of a crime, but who takes the position that he was not involved, he ought to come forward and say so, and face cross examination. We ought not force him to do so, but again, we are in a search for the truth. This is not a game. The trier of fact is entitled to all of the evidence. We allow the defendant not to testify, but the prosecution ought to be able to argue, for example: “Mr. X placed the defendant at the scene. In fact, Mr. X was arrested at the scene. His DNA is on the murder weapon. In fact, before he chose to stop cooperating with the police, he admitted that he was there. He now contends, through the testimony of Mr. Y, that he while he was there, he was not involved in the crime. He could provide evidence that could at a minimum establish reasonable doubt in your minds, yet he stands silent. Why would he do this? I suggest that he is silent because either he does not want to commit perjury, or if he tells the truth, he would have to admit his involvement. Our system of justice does not force him to take the stand and admit what he did, but you may draw your own conclusions... etc.”
This only matters if we are trying to find the truth. If we are playing a game, of course, then the result may be different.