Money. Production is far less expensive in Canada than the U.S. SG-1 is fun. It falls in that same category as Star Wars, fun, shootem up, could be a western sci fi. That seems to be the only type of science fiction anyone here wants to make. Have you seen the new Battlestar? It's a great show, and somewhat of an exception. The characters are hard, flawed and Edward James Olmos is absolutely brilliant as Adama.
Another truly awful adaption was the Earthsea mini series by SciFi. It resembled book in name only. I quit watching about 1/2 way in.
It is a good time to be a sci fi fan now. Quite a bit to watch. After a very long dry spell, with only Star Trek in the 90's.
And I guess my original premise is at least the BBC tried for the last 40 yrs.