How about no burning anything in public? It's a stupid thing to do and proves nothing, risks starting unintended fires, or people injuring themselves, etc.
Burning stuff is a classic protest move though, and that shouldn't be restricted either - within safety limits of course; i.e. Don't leave your burning flag, book, bra, whatever where it might destroy unrelated stuff.
Jews are an odd outlier as it's both an ethnicity and a religion and one doesn't automatically indicate the other. You can have people with no ethnic link who are Jewish by dint of conversation to the religon, and ethnicly Jewish people who are entirely athiest. anti-Semitism is about racism against ethnicly Jewish people, not criticism of the religion.
Or maybe you (and others here) need to re-read my response to understand what the point of it was. I understand what the person was saying, just don’t think bickering over how the Jewish people are a “multinational ethnic group” is relevant to the discussion.
Everything is important to someone, why do particular groups get privilege just because they're a religion. Should we ban the burning of Star Wars DVDs as that's a huge franchise with lots of hardcore fans who may get upset? Should it be illegal for me to burn a copy of Action Comics #1 because it's important to comic fans?
To answer your rhetoric question: Because people believe in it for some reason. If millions of people were crazy enough to think Star Wars happened and molded their lives after it, and you started burning Star Wars DVDs because you despise Star Warite refugees, yes, people would be very upset at you for doing that.
People are clearly burning religious text to demonstrate their contempt to a group of people, it's the definition of a hate crime.
Not really true, but I guess it depends on the country.
In the United States at least, burning your own book, flag, or whatever is legally protected free speech. Just as long as you aren't destroying someone else's property.
Context also matters. Burning bibles during a religious service is probably a thin line.