No, it's because of the "is it the tallest building if the height is only greater when measured from the low side of the hill" question.

Doraemon is on its 35th year. It's a Japanese cartoon about a robot cat from the future. Is that scifi? Moreover, it aired one season on a different network several years before its current run--does that count as part of the same show considering they used the same source material? Is a cartoon considered a "show" at all? (And is the Doctor Who year where they just had a couple of specials considered a year of the show?)

Super Sentai is on its 38th year and is the Japanese show used as source material for Power Rangers. Is that sci-fi? Each year they change the cast and part of the premise, but keep the general premise of five people in colored costumes who have giant transforming robots. Is that "a show" or several separate shows? (Bear in mind that no live-action show is going to last 38 years with the same people being the stars, anyway.) Is the answer changed by the fact that each show is referred to by the umbrella Super Sentai title as well as the title of the individual series? Is the answer changed by the existence of crossovers which feature both of the "separate" shows?

Also, both Doraemon and Super Sentai started later than Doctor Who but didn't have large hiatuses. If you go by time since first episode, Doctor Who is longer, but it's not really fair to count the 17 year hiatus as part of the length of the show.