At this stage it is also a numbers game.One issue that might have been mentioned, but I think that the camera manufacturers not only need to help us take much better pictures to stand out from our phones (and that is hard since well used my PIxel takes really good images) , but also be much better marketeers of said capabilities, Nikon IMHO has the worst marketing of all camera manufacturers (maybe Olympus?)
They do not have the direct reach and are not embedded in as many customers' life as the smartphone manufacturers.
Every extra effort costs them a lot more.
Fundamentally though, the great trick smartphone manufacturers have achieved is to put their camera in the pocket of non photographers, thus creating new usage cases and leading to new behaviours and needs from these millions of new users that traditional camera makers did not cater for.
(There is a great documentary that explains that the boom in film cameras in Japan was due to US soldiers who after WW2 moved to Asia Pacific and wanted to capture memories. This drove demand for 35mm cameras - I slightly digress).
Back to the point:
Their (camera manufacturers) hope was that these new smartphones users would upgrade to their "proper" cameras as the gap in quality was still wide.
Unfortunately this gap narrowed very quickly and video was soon added to the list of features which with connectivity, online sharing and online storage, low cost took the game in a place where camera manufacturers could not compete with.
Add a rapid innovation and product upgrade cycle.
Not only that but action camera makers (such as gopro) captured some of these new market opportunities, offering waterproofing, shockproof, selfie, wifi and video in a compact form.
Then drone makers captured the "mobile remote from above stunning scenes" market, stills and video.
All competing for the same wallet.
Traditional cameras only competed on image quality and low light capabilities. Not many pros and far too many cons.
And even then there was/is a learning curve coming from the smartphone world. Too steep for many.
I am amazed that they lasted so long, traditional camera makers have no pastures anew to go to.