Why? Why not I guess.
Here in the States we had a TV situation comedy called "All in the Family". I believe it was based on a British TV show called "Till death do us part". Our version here was so popular it ran for 11 years.
I never saw the UK version of Queer as Folk. I did like the US version.
As for Film remakes? I'm not sure if they make them because they have run out of ideas, or they legitimately liked the original and wanted to make a modern version.
There are alot of younger people who just will not sit down and watch a black and white classic movie. What a shame yes?
Take King Kong for example. The original was made in 1939 I believe. It is considered a classic. Virtually everyone over the age of 40 has seen it on TV at some point in their life. In 1976 they remade King Kong. I was 10 years old and went to see it. I loved it! Even today I think it is good remake despite its special effects are not as good as todays stuff. Fastforward to 2006. King Kong is remade once again. Special effects are much better, but I felt the casting was all wrong. The acting suffered. It is abad remake in my opinion.
Maybe the James Bond series is doing this too. I loved the early 1960s classic Bond movies. But do todays 18+ crowd see them the same way? Back in the 1962 Dr.No film the men all still wear hats! Women and Black people are stereotyped. Maybe todays generation just don't identify with the movies of past eras?
Another case: The 1974 US movie "Heaven Can Wait" starring Warren Beaty. I loved this movie. It was remade a few years ago starring Chris Rock. Ugh, some parts are so painful I can't watch it.