Glad to see this thread is alive and well. It has also given me time to think about the original question: "Is it time to rename the hobby?" But before I get to that, I want to build on something @KG6TGU says above. He states: "ham radio will never be as big as it once was". Well, would that necessarily be a bad thing? Is, perhaps, quality better than quantity? I would rather have 500,000 active, interested and interesting hams than 1 million simply licensed ones. I think the challenge will be, if the numbers dwindle, to keep the manufacturers interested. As the pool of clients diminishes, so too will their ability to invest in product development. Although, I have read enough comments on ham census to know that many would prefer a slower development pipeline in favor of longevity. In short, I think there will be fewer of us going forward, the goal should therefore be less about growing the hobby and more about making it resilient and sustainable.
Now back to the original question of name. It will only change if it happens organically over years. I don't see an institutionally driven one happening any time soon. The ARRL has too much invested in the name. The FCC doesn't care and won't do anything unless there is a tidal wave of influence. Who else? The ITU? Powerless to do so. IARU? That's just an extension of the ARRL. Other countries? Only Japan and Thailand have real sway in the hobby but I, frankly, can't speak to their feeling because it is unknown to me. In short, unless 'we' start to fawn over a new name, unless we suddenly discover a term that 'catches on' it won't happen. Of course, it would be fun to explore actual new name possibilities. This is not new, it has been done before, but no one has really made a serious attempt at finding and then lobbying for a change.
So, if anyone wants to start the ball, go at it. What would you see as a name that fits our passion? Note that if we get to a critical mass or good names, I'll make it into a question on hamensus.org, maybe it'll pick up steam.
I won't go first. Any takers?