Yeah I’ve seen enough horrible crashes even in giant SUV’s to know that any impact with a large truck it doesn’t matter if you’re in a 1 Ton Smart car or a 3 Ton Land Rover - the results can often be bad. Case in point, here’s my 3 series when vs the back of a semi (which is less force but more danger due to submerging under the trailer).
And yes - the driver was killed.
The IIHS gives the Smart very good reviews - http://www.iihs.org/iihs/ratings/vehicle/v/smart/fortwo and I recall seeing a video where they purposely smashed a Smart into a brick wall at a very high speed and the “safety cage” held up completely.
Again, the car has a top speed of 25mph - limiting the risks quite a bit.