There is one important thing that caused the current state of bot lane

With everyone talking about how bad the bot lane meta is now, while I think that crit ADCs getting screwed over was the last straw, I'd like to propose something else as the primary cause. Frankly it's towers being made out of wet toilet paper. In the past, one of things that made ADCs both necessary and relevant was how well they could take objectives. Back in season 3 when I started, were often the two items ADCs got first. This let them do a lot of DPS damage to objectives. Nowadays, ADCs build a lot of crit (which doesn't apply to towers) and not so much AD, so their ability to take objectives have gone down. Add in weaker towers and runes that help you damage them and other classes are now good enough for taking towers.

Really, anyone who can abuse Trinity force has a huge advantage here atm. That damage every 1.5 seconds makes up for a second item that the ADC needs enough of the time in this meta.

I think that the more recent shift to a meta where the game is decided early enough that an ADC can't get to his reworked items in time to decide the game was the necessary factor to screw crit adcs over. To be fair, stormrazor and IE would be fine for objective taking in an environment where you had the time to get both of those items before the game was decided.