ADC's feeling this overbearing is the accumulated effect of every Class update
Juggernaut update: -A champion design whose main weakness is being kited/having no effective range -Black cleaver is changed and continues to shift in and out of flavor for ADC's (Bork/BC Lucian and co)
Marksman update: -Buff to every crit item -Introduces a slew of new effects for AD items -Cait and Graves, nuff said
Mage update: -Mages get less AP and most of the battlemages get their burst/damage delayed -Subsequent changes to rylais and co make most mages spike mid game and fall of later on
Support item changes: -A TON of shields/heals -Boost to already strong healers as the new shield/heal% stacking makes them able to save ADC's from certain death
Tank update: -Item value and tank stats are lower across the board -Reworked tanks lost their steroids in favor of "anti burst" steroids (sej passive for example)
Assassin update: -Increased burst window for assassins, giving ADC's plenty of time to react -Basically gimped the entire class and made them essentially worthless imo
All in all it's the past changes and updates to items/classes that made ADC's come on on top and are currently just taking up way too much of a team's power. I KNOW this is a team game, and I like it for that, but not everyone's effectively 20% of a team's power as it all revolves around our buddies in the bot lane carry position.
I just want for everyone on our team to feel like they're an important variable for our victory, and not just feel like all I have to do is to protect MY adc and destroy the enemy one.
All in all, I think the ADC class is too archaic in their design and needs some rethinking. A position that's THIS important isn't really something I enjoy in this game and I'd rather redistribute the value I put on my teammates.
).
are dominating the game or anything

support him with heals and shields and set him up to get in melee range of the enemy team and survive there.
or 
are all designed around sustained damage and not burst.