Tanks need a lot more than Conqueror removed. This game has been shitting on them slowly since they took over top lane back around Season 3. Sometimes they would catch up all of a sudden, but the slow decline would keep pushing them down.
And that's not to say they didn't handle this decline well. They were strong for a while, and decent picks for longer, but ever since it was decided that offense should always trump defense it has been a slow march downhill. The current state of not only Tanks but all champions that do well with defensive itemization is because of this mindset, and that is the true root of the problem.
I don't even know if this problem should be fixed. Many players like this direction, even if they are not a fan of the details. Maybe players like me are just relics of the past at this point, since it's not just League that treats defense as an afterthought in it's overall design. That's not something I can truly say just yet, so I'll keep hoping for the day that defense is properly balanced alongside offense as an equal.