I lean toward disagreeing with this. I think there is still a place for the 'like' – it is distinctive in its own right (wrong as it may often seem and do). In my mind, our actions in this digital social sphere map as thus…

'reply' furthers discourse/dialogue (cost: time)

'repost' communicates agreement/solidarity (cost: reputation)

'like' signals approval/consent (cost: none)

'zap' identifies/recognizes value (cost: money)

Our correspondence, kinship, and connection (whether IRL or not), need not always cost. We ought leave some space for the informality.