This is what happened:
Riot promised a tank update to appease all the ADCs complaining about tanks. Then they started brainstorming and realized that tanks are much harder to rework than they thought. They had a deadline to roll out changes way before the summer split. So when it became crunch time, they just put out anything regardless of whether it was good or not.
A prime example is the sejuani passive only being able to be used by other melee champions. Does that feel like a proper finished product to anyone? I hope not. What it feels like is that they had an idea and said "wow this is strong if everyone can proc it....but the deadline is tomorrow. Lets just make it melee only."
Maokai ult is a bigger, clunkier, slower Nami ult. They took out what made him a good tank to do it, but forgot to add anything else in for damage mitigation while simultaneously making his passive heal significantly harder to proc. What is this a response to? People complaining he's too tanky. So now he has nothing in his kit that really makes him an effective tank while having all the shortcomings of a tank kit. His W speed is also ridiculous. Its so slow now people can walk/dash you into turret range in lane without a problem. Oh and they moved the % health damage from his root to his E.... An ability that doesn't get a lower CD as you level it. I think its 12 seconds. Maokai is dead when these changes go through.
Zac is the biggest offender in terms of ADCs complaining about the damage of tanks. Riot thought his kit was boring. So what did they do? They changed his q so that it only hits the first enemy in its path and then made it so you don't get the full benefit of the skill unless you find yourself another enemy to hit the 2nd half so you can smash them together. I watched 2 full game plays and this was only accomplished on an enemy CHAMPION once. 99% of the time, its just people nailing the first half and walking with the enemy champion like a dog ona leash till they walk away. Then there's his ult, which was fantastic. Now the PBE version is a total piece of shit. Here's proof: Using the ult removes movement impairing effects...BUT then zac has to sit and channel his ult for up to 2.5 seconds. So you give him movement impairment removal but then you make him sit there anyway. Zac is in no way stronger with this rework. Everything about his effectiveness is now so inconsistent I'm fairly sure this is going to end up in the growing pile of rework failures.
Sej is probably the best of the reworks but still not strong. The best thing about Sej outside of her ult was spamming slows on her e during combat to apply mass CC to the enemy team. This was fine when she was created, the problem was that being in combat long enough to make use of a skill like that doesn't work with damage being off the charts the way it is now. As a result, she became a one trick pony (her ult). Her new kit only has one slow and its tied to the ulti. The slow on her E was straight up the best part of her kit. Now 25% of her kit's use is dependent on getting tons of stacks on a single person before you can even use it. Braum's passive is about 10x better than this ability. They literally took the only champion that was in line with what they said they wanted (high cc and low damage) and removed all her consistent CC and reduced the CC on her ult while giving her passive proc the ability to do 25% max health in magic damage. So they essentially did the exact opposite. But just to make sure people wouldn't play her as a serious damage dealing champion, they removed the AP scaling to her W so even playing her that way isn't an option.
So basically the end result of the reworks is this:
Maokai: Formerly the best tank in the game in terms of damage mitigation and sheer difficulty to kill. Now has no damage mitigation, a slower, crappier nami ult with a root, damage that depends on people face checking the bush in lane without minions walking in first (sapling), a snare that has such a low transit time that it literally can hurt you more for landing it than it helps you in lane, ridiculous cooldown on his big ticket damage item. This is by far the worst of the 3.
Zac: Formerly the most complained about tank by ADCs in terms of damage. They changed his q so now you almost never are able to get the skill to work to its best. Took away his aoe slow with decent duration and made it only work on the first enemy hit (which is difficult because its a narrow skill shot now on PBE) then paired the full extent of the skill's use on the ability to be able to target another enemy (inconsistent). Then they made his ult this paradoxical piece of shit that removes movement impairing effects but then forces you to channel an ability for up to 2.5 seconds.
Sejuani: Formerly the CC queen of tanks who at best needed increased damage to jungle camps to be completely viable and in line with their aim of reducing tank damage while increasing tank CC/disruption/team fight ability. The rework removes her most consistent CC (the slow on E) and randomly made it dependent on stacking which requires the help of ONLY melee team mates auto attacks. The ability is dwarfed in effectiveness by Braum's passive. But then they gave her the ability to do up to 25% max health.
These reworks are an abomination.
Sejuani is reworked in PBE server, and she is not Sejuani anymore that we knew. Her ult stuns only one champion now.
