They weren't the only media organization in the building, and I presume they do indeed have offices in cities where major news repeatedly breaks.

There's an undercurrent in your comment of blaming AP for having a presence in Gaza, yet this was not an accidental strike. AP says that Israel gave them advance warning of the attack.

https://apnews.com/article/media-israel-middle-east-business...

They don’t mean because of material damage, it is due to the clear signal sent that Israel is willing to use military action against the media. obviously this is going to reduce the coverage as not all journalists are willing to risk their lives to cover a story.