This is the whole point. People do not need to 'take care' when expressing outrage at what is internationally considered genocide in case someone throws a slanderous accusation of antisemitism.
Real examples of anti semitism and any racism should not happen, but for too long there has been a conflation with opposing Israel and it's supporters and antisemitism.
It's is right and proper that people question accusations robustly and are not scared to stand up against injustice because they are scared of being labelled antisemitic.
'take care 'almost sounds like a threat, because for a long time people who stood up for those being mistreated by Israel were shut down, being a labelled a racist/antisemite can have rightfully have a big impact on someone's life/career etc. That is why it is so appalling that people throw the term around every time someone challenges their political/ideological allegiance to Israel.
People have had to be pretty brave to stand up for their beliefs with this threat hanging over them.
That is not to be confused with antisemitism aimed at people because of their religion and it is important that such an awful accusation isn't constantly used to shut down legitimate debate.