Yeap, the test ist too simple. I know some teenagers those will choose to be seen as sociopath (though they are not) and they will do whatever to get the max score on this test.
Sociopaths easily fool even "professional" psychologists and psychiatrists. This explains why it is frequently undiagnosed.
IMO, to really diagnose it with any degree of accuracy would require electronic monitoring for brain activity or involuntary emotional responses --- or the lack thereof --- while being exposed to various stimuli.
> Describe in single words, only the good things that come into your mind about your mother.
-- Voight-Kampff test from Blade Runner (1982)