The nerf to Sejuani is not valid to her other sub-roles

I play Sejuani a lot. She's my favourite because she fits really well in several roles.

If I see an enemy melee AD TOP, I can go top and probably do well. If I have to be a support, she's fine as a support with tons of CC. If I have to go mid, okay not so viable, but still workable in burst match up.

After the nerfs, her other roles get nerfs for no reasons, because those don't build Cinder. Top lane is the only one I want to talk about as it took the greatest influence.

W is her main and ONLY tool to trade. The nerf to her health % damage makes her reasonable harassing falls behind. She is already a situational to pick.

I don't know why Riot decided to nerf her whole kit instead of only looking at her JG path. Is it what they call diversity?