League of Legends is so boring compared to how it used to be in 2014-2016
Now its just a battle royal game with everybody having to build a certain selected rune page in order to not be trolling, have to build heavy dmg to actually do anything.(xerath supp and brand supp are picks that spawned out of need for more dmg)
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for example.
Also tanks lack any sort of useful meaning at this time since you just ignore them. In the past with conqueror and all the tools that were out to shred tanks made them easy to kill without caring but now you just ignore them.
Which is worse because at least conqueror encouraged people to attack tanks as opposed to them building all the tankyness in the world with no effect on game outcomes.
Runes are so calculated and there's only one best page for every champion if not only 2 but with no same result or increased efficiency of the main playstyle but rather another.
Late game power list(its listable at this point)
- Assassins/Skirmishers(They make targets useless long before late game and if its a skirmisher/assassin then they will scale endlessly where no body will stop them from winning/yasuo-fiora examples)

- Juggernauts and Divers(yes i fought against a garen/darius bot lane before and its cancer you have to camp top or mid and win fast)
2.5. Marksmen(they aren't as good as diver/fighters and slightly better than damage mid laners so they are in between;very squishy and easy to shutdown if you have a jungler or use cc on them ;)) 
- Damage mid laners

- Battlemages(honestly just worse damage mid laners)

- Supports(average non duo enchanters)

- Tanks(5th place if they don't ignore them)

- Ivern(LOL)

In opinion the reason tanks get ignored is because 90% of champs and new champs are over buffed monsters with high damage and CC all in one with little drawbacks. Items aren't the issue but when overbuffed people buy high ad/ap items then they benefit way too much.
But no you can't go yasuo support as a good pick, you still have to play by the rules because thats undervaluing meta(Karma is just fine and has crazy ratios) You don't necessarily need a marksmen on adc because its just someone who will do damage efficiently or scale hard so garen and yuumi comes to mind or a mage with good range is generally easier to play since you don't have to kite.
Mid is best for damage mid laners, but i must say that the mid laners that deal a lot of dmg with high defense skills tend to win easy in the early game like galio/exhaust-barrier vs zed for example.
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