Real life examples from Europe, where a "closed" road is showed as a positive message.

Italy:

Denmark:

If I were driving I would take this to mean crosswalk or watch for kids due to having seen similar signs.

I think it would be great to gain a new meaning however when posted in the middle of the road.

That's the criticism in this picture. The sign is vehicle-centric where it should be explicitely pedestrian-centric.

The road sign is technically correct, but it looks at the situation as "car by default".

It reinforces the idea that in order to accommodate pedestrian friendly places, we must punish drivers by restricting them from going where they would otherwise be allowed to go. It assumes that cars are allowed to go anywhere, unless explicitely stated otherwise.

The way you communicate ideas is important if you want to get people on board, so maybe it is better to say the road is "open to pedestrians only", rather than "closed to cars"

The sign is addressing cars and for cars it's closed but from a human perspective, it's open

Better than “self-driving” cars.