Most images produced and consumed today on smart phones do have view-by-date, which would be about 15 sec after posting on social media. Timeless images, however... 
I do own a smartphone.
Never quite been able to bring myself to use it as a camera though...
I don't know what that means for what I shoot though.
I have certainly shot a lot of rubbish that would not even warrant 15s consideration on social media or otherwise.
Thankfully, though, I have shot some interesting and worthwhile stuff over the years.
Also, interestingly, I have a friend who was a press photographer who now shoots mainly sports for Getty and also works independently for certain press agencies. He uses his smartphone a lot, on a day-by-day basis, and shoots whatever catches his eye. The IQ is not what his DSLR produces but as an exercise in framing and composition he certainly keeps his hand in.
I think there might be a lesson there...
Tony Jay