What does a support meta look like?

How could Riot accurately create a 'support meta', similar to how they have created the 'tank/marksman/mage/assassin/ .. metas' in the recent past and present? .. And without simply making supports into more powerful utility mages and tanks.

One interesting mechanic that has popped up recently is the idea of linking characters. Kalista, and more recently the Taric rework, Zeke's Harbinger, .. These things cause a necessity for a support/carry relationship. I would like to see more things like this come up in champion kits, maybe even more items that have passive effects that only work when within range or attacking in coordination with a 'linked' ally.

Otherwise, giving massive shields, heals, insane crowd control/stuns/slows/displacementsl, buffs/debuffs, ... would need to be carefully designed to be geared toward a support role instead of being stronger in a solo position.

Tell me your ideas or tell me if you think this is even possible.