I admit the phrasing of the excerpt does look vague out of context, but it is about the collective of Jewish people. That is suggested by the excerpt saying "Jewish citizens" rather than "a Jewish citizen". It should also become more clear if you click through to the original and see all the other examples are about the Jewish people as a collective too. So yes, this text is specifically about the "because of" even if the excerpt doesn't make that explicit. It is not saying that any accusation of disloyalty is inherently antisemitism. For example, if a Jewish American citizen was arrested with real evidence of them being an Israeli spy, there would not be a serious discussion of whether the arrest was an act of antisemitism.
This is a pointless concern because "the excerpt" has no motivations behind it that were imbued by its author. The only reason it exists as an excerpt is that someone pulled it out of its original context. Either go to the source and read it in context to get a better idea of the motivations of the full text or attribute the motivations to the person who decided to excerpt that specific text.
You specified that. The excerpt did not.