I like that people think there is a big mystery behind support characters and one Riot unlocks it, the role will be forever changed. Being the ward ***** is what a support does. It helps win games. There's no secret. Letting the carry farm up is just what you do. It's like that with every MOBA. Stop kidding yourselves and thinking that supports should get farm.

Buffed scaling or better item incentives couldn't help, once they start having reason to farm over someone else, they're no longer support champions.

instead of last hitting giving just you the gold, how about it gives your entire team the gold (both for champion and creep kills)
(naturally the gold from cs/champ kills should be decrease to balance out that fact that everyone on your team is getting the gold)

this would solve 0cs support because it doesn't matter if 0cs or 100cs, everyone gets the same gold therefore support players gets the fun of buying items just as the much as the carry

it would also solve some other underlying problems too
1. it is much harder for hard/hyper-carry to farm up and kill everyone because the gold is distributed to the entire team; hard/hyper-carry getting fed is more frustrating to play against than to play as
2. prevents hard/hyper-carry from being completely shutdown and being useless; playing a useless champ is much more frustrating than the fun that comes from shutting him down
3. completely eliminate rage that comes from bad players complaining about ks in low elo or good players complaining about support getting the kills in higher elo