It can't miss a person when the sensor is right at the desk. And from the desk, a sensor can turn off peripherals as well, like monitors and task lights. Active IR, scene control presets, HVAC control. The technology to do all of it is here today. The biggest obstacle is education, without a doubt.
People have to be aware that there are more sophisticated systems.
There is a tendency to install systems that have the lowest first cost and still meet standards or codes. People have to be educated that systems are available which provide benefits beyond the lowest cost products. Obviously they cost more, but they have benefits beyond saving energy. Once people understand the additional benefits, people will install better systems.