Janna is, as a statement of objective fact...
...the most broken Champion in the entire history of League. 6 full seasons and she's not once fallen below 54% winrate and 20%~ pickrate. She's the single most frequently and heavily nerfed Champion ever and still sits at a popular playrate with above-average winrate. She's the easiest an most reliable Champion to fully stack
on, save for maybe Lux. No matter how the meta shifts, there's still no real answer to her either. Strongest disengage in the game so diving and engaging is a no-go. Lane trading is a no because spammable shield that also gives her adc more ad. Siege isn't gonna happen because she can put her shield on turrets (and they get bonus ad too.) Rotation and splitpush comps don't work because she can use her passive to boost allies around the map. The closest thing to a valid option is poke comps, and those are dumbed down by her shield as well, and if they're really desperate for anti-poke they can just take Yasuo mid. But, you can't dare say Janna is broken because "she's just a support, you're why nobody likes to play support shut up you're wrong"
Am I crazy or is Janna's kit in it's entirety just stupid?

, but after that? Nah.
also works wonders with her as she has the highest total mana without building any. She is also one of the few people that can stack
boosts both of these, so it's a must.
for the mana sustain and cooldown,
because gotta go fast, and
,
, and a trinket).
or
were broken, everyone was complaining about them. Simply being a support doesn't give them immunity.