Unpopular opinion: I find simple tagging and non-obscene graffiti in general less offensive than the spam flyers and company logo stickers everyone sticks everywhere. At least where I live the latter is also way more common.
A lot of those nice “graffiti” works are actually commissioned by the building directly. It’s not usually something that someone does overnight. They’ll set up actual scaffolding and cordon the area off while the artist works. Because it’s an actual art piece, not just a random tag.
I'm not from Berlin but I do live in the city. You absolutely see graffiti this elaborate in the wild. In fact it normally comes in on top of all the random tags and mess if it never gets cleaned up