I wouldn't lay this all on Apple (and you may not be): we've crested the feature curve on all mobile platforms. There is just so much you can do with today's hardware (meaning: a handheld PC as opposed to a holographic communicator or whatever is Mobile 2.0). With millions of apps, most significant innovation on this platform has probably already occurred. Plus, we are now used to these devices and the things that impressed us 10 years ago (pinch to zoom, for example) are just considered commonplace - because they are. Someone will probably come up with some whizbang app that does something novel, but that will be the exception rather than the rule. Siri Shortcuts has potential to reshape how we interact with devices, from an app-based interaction paradigm to an intent-based paradigm, but its too early to tell if that will happen and whether it will be revolutionary vs. evolutionary. One belwether will be if Google/Samsung attempt to emulate it.
Bottom line: mobile devices are now commodities rather than spectacular and new. Something big will have to break the innovation model, much in the same way the original iPhone broke the previous model of handheld device usage.