@Riot Maokai No MR Scaling?

I'm slightly confused by this and would like some clarity. It certainly seems like maokai, being a tank, would have at least some small mr scaling. Other tanks like malphite, sion, voli, rammus, nautilus, even jarvan have about 1 mr per lvl scaling. I would just like some clarity because this really doesn't fit with maokais thematic at all. I mean, hes supposed to be a powerful forest spirit fused with the tree of life (basically). It could be that riot feel his kit is loaded enough to not warrant mr scaling. If so, I would like to hear that.

Thoughts from the community?