That is so not true! If it wasn't, CLAMP wouldn't continue their relationship in Tsubasa! As for people who hate Sakura and Syaoran's relationship, I have come across them on the Sakura Hybrid website. Their moderator, The Pie, started a post asking what was your favorite couple in CCS. He said that he liked Sakura & Tomoyo, and then asked what everyone else asked.
At least 95% of the members said Sakura & Syaoran were the best couple and he wrote a rant about what a jerk Syaoran was and that he'd ruin Sakura's innocence! He insinuated that Syaoran would take advantage of her! I didn't really say anything to him, but in a moment of indignancy, I made sure that my avatar was of Sakura & Syaoran.
Also, my sister hates one of my Sakura & Syaoran music videos(I didn't make it, I downloaded it) because there is a scene from episode 57: Sakura, Syaoran, and the Elevator, when Syaoran was at the fountain and Sakura & Tomoyo came, and Syaoran hid behind the fountain and looked over the edge, she said that Syaoran was a spy and perverted. I hit her on the head and shut the music video off. After saying that about 5 times, she knows not to say that anymore. I don't know what I would do if anybody who wasn't family said that they hated Syaoran. At least my other sister likes that video, and even that episode!