Timewalking Raids

Why do we not have these?

I am an idiot when it comes to WoW so it takes me an age to not be shit at them. Timewalking dungeons are Nerfed to Fuck, it would be awesome to have raids as an option for Timewalking.

I know you can do custom groups or a specific NPC for this kind of thing, but it's the easy LFG/PUG plus TW points I am really into.