Alt text: Photo of the backside of an advertisement billboard in Lisbon with graffiti writing "TAKE THiS SHiT OFF WE WANT TREES!" There is a busy street with cars in the background, and two people in the front that seem to be indifferent to the text.
Before I read the text I immediatelly thought "I know this place" and then spent several minutes examining the photo and trying to confirm if it indeed was Campo Grande in Lisbon or not. (Not a single car license plate is visible, by the way).
Mind you, if it is the place in Lisbon I think it is, which (you can't quite tell it from this angle) is a large 3 (4?) lane roundabout with constant traffic, the comment is probably about the traffic heavy roundabout itself rather than the billboards.
If it is so, I wholly agreed with it: Portugal has a huge problem with its insane car-oriented mindset (it's even a social signal of success).