Maybe it’s a product of its time, but I had a week off in 2009 and went through the first two seasons very quickly that week. IIRC, it being on Netflix in the early days let people binge it and contributed to its success while it was still airing which made it very popular. I’d venture to say it may be one of the first bingeable shows, but because that wasn’t a thing at the time, it didn’t follow the bingeable formula, so maybe that’s why it doesn’t feel like modern bingeable shows?