Because their definition of anti-Semitic is someone who will not support thier genocide in Gaza. To them, you either wholeheartedly support Israel killing anyone in its path to expansion or you want to put all the innocent baby Jews who don't have a speck of darkness in their little angelic souls into gas ovens. There is no in between. And they're successfully making it such that there is no in between... except not in the direction they want.
My opinion of the Jewish people was neither positive nor negative before this incident. They're smart, resourceful, but manipulative and closed. The most positive memory I have of them is that my grandmother spent the last decade of her life frequenting a club largely populated by old Chinese and Soviets. She had a great time there chatting; they gave free high quality food with extras to take home, there were lots of games in the recreation room and they had many outings all free of charge. They could even win cash prizes in the games they played. She had many friends there. When you entered the front door, there was a huge mural of all the veterans in the club from China and Russia who fought during WWII. The establishment was paid for by a Jewish businessman who wanted to thank the Chinese and Soviets for fighting on their side and the Chinese for saving over 20K Jews from the holocaust. Now, looking at their actions today, I think that saving them turned out to be our sin.