My actual argument is this: When it comes to book burnings, since there’s no harm done to anyone and no call to harming anyone either, the freedom of expression should be given priority

Those on the opposite side would disagree. There is harm being done. not all harm is physical.

This would be different if there was something harmful being done or incited,

The act of burning it is incitement.

but the only things that really are in danger here are books and the only people taking offense with that are people who think specific objects should be treated as more than a book by everyone in- and outside of their religion.

As mentioned many times. You are not allowed to burn flags of forgein nations.

You can use the exact same arguments. It's just cloth that's in danger. Only people of that nation is taking offense. why should everyone outside of their country have to care about their flag?

Why should their sensitivity triumph that of my right to burn flags?

In this case. We already have a standard that is so similar to what is happening.

a flag is a symbol for a group of people. so is the quran.