Is the hypocrisy being portrayed here that they should agree criticism of Israel is anti-semitic? Or they should disagree criticism of China is anti-Chinese?
People are quick to tie the name of a country or nationality directly with the culture/peoples that said name was derived from (or vice versa). Unfortunately to many people, "Chinese" as a nationality is the same as "Chinese" as an ethnicity/culture/language (rather, a group of ethnicities/cultures/languages since "Chinese" is used for many groups, though it's mostly Han and relatively closely related groups), and their logic is criticizing or denouncing China is an attack on Chinese nationals, which is equivalent to attacking ethnic Chinese.
Sometimes their logic is – actions against China are meant as a way to undermine Chinese influence for the purpose of committing hate crimes or genocide against Chinese (China is totally the protector of ethnic Chinese in this case). Basically similar to Russian bots' favorite excuse but rebranded.
With Israel it's a lot easier for them to separate "Israeli" (the nationality) from "Jewish" (the ethnicity & religion) because (in English) they're completely different words, so it's a lot easier for them to tell "Israeli ≠ Jewish", as opposed to their head exploding when they think "Chinese ≠ Chinese". It's easy for the uninformed and malinformed (and those who benefit from such a viewpoint) to rationalize the sentence "attacks against Chinese are discriminatory against Chinese" but less so of "attacks against Israeli are discriminatory against Jewish", even though in both the first term is a nation or nationality and the second term is for a variety of ethnic groups that isn't necessarily tied to the nation and describes many peoples who have no connection to the nationality.
In Chinese you may call someone of Chinese descent huaren, but you generally use zhongguoren for both Chinese nationality and ethnicity (with zhongguo being "China", essentially "China people"), while Israeli is yiselie and Jewish is youtai with no chance to conflate the two. The Chinese bots get confused by the same language issue too.