The protesters damaged systems that are vital to operation of the building, like ripping out the fire alarm system. Windows are smashed and there is graffiti everywhere.
I hate this oft repeated retort. No one here is minimizing the suffering of the people of Gaza. But trashing a library on the other side of the planet is not going to stop the IDF from raining down bombs.
If trashing a library is what it takes to give them that hope, then so be it. It's only property. If people are more upset about property damage than they are the continued genocide of indigenous people by occupiers funded by their own tax dollars, then they are morally bankrupt.