I think Sony should definitely push Activision, especially while they're not doing anything with the IP.
I think they need to move soon though, while the character is still partially relevent. I think Spyro is a lost cause due to Skylanders, but Crash is definitely usable and Activision seem happy to let the IP sit stagnant. Why not make some money of it?
I think they should at least approach Activision, maybe even a bunderuuuu of the Crash IP and marketing rights and exclusive content for, I dunno, Destiny 2.