Graffiti is considered vandalism in most cases, and thus deemed to be temporary as it’s likely to be removed. Niantic have been removing graffiti wayspots recently for that reason.
Additionally it technically doesn’t have safe pedestrian access as it’s on the road side rather than the pedestrian side where you’re stood.
To start with safety first, this is the entrance to a building complex. Where I’m standing is a pedestrian walkway, and you can even see the yellow car bollards.
At least 50% of the wayspots are murals and graffiti. This particular wayspot has been in the game for at least 7 or 8 years. What everyone suspects is that it was manually reported because it’s difficult to reach by car, and it might have bothered someone.