The interesting thing here is that an identity is represented by an image ("avatar"). Normally you can't get enough combinations with such a scheme and still produce a distinguishable image. Perhaps those long hex numbers shown in the screenshot also represent identity?

Another interesting thing here is that the RSA keys are 1024 bits long. It is fairly unlikely that some entity like the NSA is going to expend a Manhattan Project level of effort to get the messages of one individual (it would be cheaper to use other methods) but they in theory could. Most just make RSA keys 2048 bits long and accept the wild overkill.