First people complain that tanks never die but then complain about damage creep.
The two aren't mutually exclusive (as you are trying to imply). Quite frankly, the main victims of damage-creep are squishy champions since it tends to change the damage they receive from threatening to insta-kill levels.
If every champion has rather high damage, then that pretty much removes the need for burst-focused champions; why bother picking a champion who is focused on bursting down a target (i.e. Brand, Zed, Akali) when others are capable of doing the same with more durability/utility/safety?
There is no point picking a champion who can deal 150-200% of a champion's health in burst damage if another option deals 100% of their health in burst damage while providing more options.
Second diving bot has always been a thing because there is more people there along with a dragon so its just a much more valuable lane to focus.
It has always been a thing, but it is pretty much the only viable strategy at the moment since a successful gank bottom lane will provide two kills, a turret (with First-Blood gold) and Dragon. At this point, the team which orchestrated the gank will have a massive lead and their bottom lane will be free to roam and pressure elsewhere on the map.
Third people have been bitching about how Cait and Twitch are op but then bitch about how ADC's are trash.
ADCs, as a role, are weak at the moment because they lack influence on the game. They are late-game carries and the game is often decided long before they can make an impact by the performance of their allies and enemies (primarily, the mid-laners and junglers). While they can be rather oppressive when they are ahead (i.e. on the winning team), they are at the mercy of their teammates (and opponents) to reach that stage rather than having control over it.
