>>638702The implication is that modern people are on their phone all the time, texting or browsing reddit, so they don't need to look at their watch to see the time because its already in front of their face.
If you're using your phone to tell the time by taking it out of your pocket, clicking it, putting it back in your pocket, then what you have is a fancy $500 touchscreen pocket watch. In that case especially watch is still relevant and has all the advantages over a pocketwatch that it has over your phone.