Maybe I am being naïve, but I honestly think it would have been considered ok as a tribute to something Walt said more than Song of The South given the song/phrase is not nearly as iconic as Zip-a-dee-doo-dah.
It may be a tribute to Walt, but is it a reference to anything he ever actually said?
It certainly felt like a new quote to me the first time I crossed it during the initial Storyliving announcement. We all know how Disney PR likes to trot out old out-of-context Walt quotes to justify controversial changes, so I just assumed this was one of those, albeit linking it to a property that modern Disney has always kept its distance from.
While I don't consider myself to be a Walt scholar, I've read a couple biographies, seen nearly every filmed interview he did, and have read extensively about Disney (the company) during his lifetime. And despite this, I've hardly ever seen any concrete references to his time spent in Palm Springs. The way its always referenced as an indirect quote is especially suspicious to me.
Other than his tie pin from the Smoke Tree Ranch being included on the Partners statue, he never seemed to bring it up. I also suspect the STR pin's importance may have been overemphasized after the the statue's creation, since he only seemed to wear it in a handful of interviews filmed around the same time (possibly even the same day/week) in the mid-60s.
Granted, although Walt often referenced his childhood as inspiration, he did a good job of keeping his personal life as an adult private. For example, it wasn't until several decades after his death that historians agreed that Sharon, his eldest daughter, was adopted. So perhaps he was just keeping his personal vacations out of the spotlight.
And perhaps the term "laughingplace" was much more common then than it is today, and the association with the song is a result of the song's popularity not the origin of the term (similart to how "let it go" will forever be linked to the song). But that particular wordchoice, highlighted by quotes and everything, really raised my suspicions about the Walt story's origins.
Disney loves to invoke Walt's name to try and make an otherwise-questionable decision untouchable by the fans. We've seen it countless times, especially with the "Disneyland will never be complete" quote. To me, this one always seemed more like wishful thinking from PR than an actual reference to anything that's been documented in the past.