Ray Mears is at least bringing important (often purposely overlooked) aspects of history, and historical characters to the attention of the public. Even if you don't like his presenting style... you have to respect what he has managed to do.
Without Ray, I would never have known about Amundsen, Lettow-Vorbeck, the heroes of Telemark, Rogers rangers, the northwest passage adventurers...
Also, the 'hands on' insight he has given us into indigenous cultures and hunter gatherer societies.
He took stuffy old museum artifacts and dusty library books, and bought these things back into the real world, by encouraging people to 'go out' and try to acquire the skills for themselves.
Tasting birch sap, smelling clean wood smoke, using a knife/axe, butchering meat...
you have to admit it beats just watching David Attenborough on the sofa!