Given existing tendencies toward attempts to control or block public spaces(gating/hiding rights of way, rentacoping undesireables, etc.) and the embrace of things like ‘privately owned public spaces’ and just straight up private spaces that look sort of public(eg. malls vs. shopping streets); the last thing we need is a cheap, powerful, tool for essentially being able to paint private law backed by significant civil penalties, risk of litigation, and probably every automated takedown bot on the internet, onto public or public accessible spaces.
And that is exactly what a finding against Mercedes would do: provide a presumptively authoritative copyright claim against anyone taking a picture(or even doing something like leaving a voicemail if the place they are calling from has copyrighted Muzak) in any space they’ve been able to splash something that meets the minimum standards of creativity for copyright protection.
There’s not even an obvious reason why public art would be exempt: you probably don’t own the copyright to your wallpaper(if your house has some), or the pattern on the cloth your pillows(and potentially clothes, if not solid colored in a non-pantone-owned shade).
If an incidental glimpse of copyrighted work is sufficient; the rightsholder gets significant leverage to impose law-by-contract over a broad swath of activity. That will go at least as well as mandatory binding arbitration.
If anything, the only safe option would be an explicit statement that by making public art certain rights concerning control of derivative works are disclaimed and cannot be retained(there’s a stronger argument, though not zero risk, for letting people in private contexts negotiate; but in a public context a failure to get those rights disclaimed is a unilateral imposition on everyone who uses the space in the future, not good).
Hopefully the artists got paid adequately, if it was a commission; or got whatever they sought if it was inspired by other motives; but allow them to usurp control over all public space in line of sight? Hard nope.
