Trying to get to the root of a commonly expressed anti-intellectual bias, a fundamental misunderstanding of what constitutes “science” and (exhaustively) explaining that what mythbusters has done with human remains is absolutely inline with the normal treatment for human remains in science is fair justification to argue a semantic point. Fundamentally though, mythbusters is science. Even by the definition you provide for hard science, it 100% fits with the process mythbusters used. Formulation of hypothesis, bias-controlled experimentation, reporting of process and results. That’s all science is (and even including ‘bias control’ is possibly too restrictive to meet the common definition).

If you use the definition from the non-simple wikipedia article,

Hard science and soft science are colloquial terms used to compare scientific fields on the basis of perceived methodological rigor, exactitude, and objectivity. In general, the formal sciences and natural sciences are considered hard science, whereas the social sciences and other sciences are described as soft science.

the presumably accidental misuse of a highly colloquial term is quite evident. That obfuscation of meaning is one of the primary criticisms of Simple Wikipedia, in fact. This is again a commonly repeated piece of anti-intellectual rhetoric, wherein one assumes that science can only be done by those with accreditation, grant funding and a sterile white lab (obviously this is a slightly hyperbolic exaggeration of the specifics for comedic effect). Mythbusters is undeniably science, just as much as it is undeniably entertainment. The two are not mutually exclusive, and flashy editing does not impact the rigour (or lack thereof) of their methods nor the validity of their conclusions.