I dunno. I've only been on Lemmy for a few months. Some people really enjoy being edgelords on the Internet. Without the context of what particular wall it was with bullet holes from summary executions, it could just as easily been a farmhouse where Black and Tans murdered someone for speaking Irish, to me.
Context matters and I didn't have it - might be good to ensure that everyone is on the same page before deriding and belittling them. The world's fucked up enough as it is without going off on each other or assuming malice when ignorance is the cause.