Thank you for reaching out! No, I am not currently working on it.
I remember spending quite some time on the wiki debating over which tag to use. There is natural=fell, tundra, heath & scrub. In the end I read the descriptions, compared the images and apparently considered tundra/fell appropriate. 
I do see that those are not rendered by OSMCarto, which is unfortunate.
In general, I would still vouch for my decision of tagging (maybe fell is better), instead of scrub/heath. Yet, I certainly won't start re-editing, should you feel compelled to change the tags. I can have a better look at the inagery and wiki later, this might shed some more light on why I arrived at that decision. 