Why should I have to focus down the support rather than the ADC


Can these be junglers now? Because they can still 100-0 someone throughout the game on a low income 


Can these be junglers now? Because they can still 100-0 someone throughout the game on a low income 
Those aren't supports, they are mages being played bot lane in the support role. The reason they are being played in place of real supports is for the exact reason you mentioned. They have enough damage to kill people on a low gold income. They are balanced around being solo laners. The tradeoff for their high damage, range, and hard CC is supposed to be their lack of mobility, reliance on landing skill shots, and dependence on using abilities/mana for damage and to farm. In a duo lane, these weakness are made up for, while their damage and reliable kill combos are still enough to be stronger than a traditional support in many matchups. The problem is not that "supports are OP". Just because people play them bot lane does not make them supports.The problem is that these mages need to be rebalanced with their support gameplay taken into consideration, while traditional supports are reblanaced to deal with these mages should they show up bot lane.
unfortunately though, whenever a support is rebalanced, it has massive consequences.
let's look at say if traditional supports were buffed to contend with their high damage counterparts, well, then riot has to deal with the off-lane support issue
then when riot nerfs mages from support lane, the mage either gets broken or a new item is implemented or changed that breaks everyone or another champion in specific
it's a vicious cycle