You didn’t need “pro vision” to see where this was headed from launch day. It was dead on arrival at the price point and lack of a killer app. End of story.
The need to define a product by a "killer app" is overstated in my opinion. These are computing platforms and aren't defined by a single killer use.
iPad didn't have a "killer app", Steve listed 7 different things (Browsing, Email, Photos, Video, Music, Games, eBooks) that were already possible on other platforms, but were experienced in a new way on a tablet.
Steve explicitly stated that for the iPhone, "The killer app is making calls", which turned out to be the least important thing about it.
Spatial Computing frees digital content from flat screens - the platform and UX is the killer app. Even windowed 2D apps can be wherever and whatever size you want. Your Mac's content can be wherever and whatever size you want. Spatial home photos and videos are more vivid and emotionally resonant. Immersive videos are jaw-droppingly good and are especially great for sports and concerts. Watching movies and TV is basically like having a private theater where nobody bothers you and you always get the best seat. 3D assets are actually 3D, so you can inspect objects from all sides, get a true sense of scale, and place them in a physical space. It enables whole new gaming experiences, whether native spatial content or streaming from Steamlink.
Yes, it's too big, too expensive, with too few apps, and not a commercial success. But lack of killer app, dead on arrival, end of story? It's Apple's biggest technological breakthrough since the iPhone, hands-down.