In terms of expended effort, posting an emoji in the timeline of a girl who you find physically attractive is even more low wattage (and about as effective) as changing your avatar to the flag of your preferred victor in any one of the many exciting wars that are collectively dragging us towards a state of global conflict.
It is hard to determine quite how Greer expects to develop meaningful connections from these dalliances along the attentional fringes of a various attractive young girls. I can only assume he imagines that, if he repeats the same tactic on a large enough scale, then one of his attempts will bear fruit. I am betting that he runs out of rolls of the dice before this happens, and that he would have a greater (albeit slender) chance of conditioning his body to a point where he can slobber to his heart's content on his own rancid penis.
If he was capable of empathy, which I don't think he is to an extent where it would be useful, he might view his unanswered exchanges from the perspective of someone who was born with pompoms where their hands should be: How is a hot, young girl supposed to respond to an emoji, perhaps accompanied by a few carelessly tossed-off words? Where do you do from there? If hitting on women was as easy as bombarding them with mutant hieroglyphs, then every available heterosexual man on the Kiwi Farms would be up to the hilt of their balldos in cheerleader pussy, and these forums would echo with the lonely sound of Josh's digital footsteps.