I admit having a "like" button would be helpful if folks are in a hurry and trying to catch up on their phones (me for instance, when I'm in my tent for a week and miss 500 posts while I'm gone).
But I agree with Shamus in that it might discourage people from actually commenting, even if it's only a few short words, and those words can often mean a lot in response to a comment or photo any of us have posted. Commenting also prompts responses from the original poster, and often then more interaction leading to friendships
