Why are Champion Mastery tokens limited to only classic SR?

In light of the recent API changes to Normal game stats visibility, Mastery token availability should also be reevaluated. It makes little sense not to have tokens available from all permanent League modes (i.e. SR, TT, and ARAM). At the very least, tokens should be available in ranked Twisted Treeline.

From the Riot Developer data policy

Our intention is that normal games are similar to pickup sports, where you're there for fun and are trying to win, but the stats ultimately don't matter.

From the AskRiot post on Champ Mastery for ARAM/TT

We want to maintain mastery levels 6 and 7 as achievements specific to high performance in competition, so they will only be achievable in SR modes.

So Normal SR is competitive enough for Mastery tokens, yet not competitive enough for stats. Meanwhile, Ranked TT is competitive enough for stats, but not enough for tokens?

Riot has enough confidence in the post-match grading algorithm to award Hextech chests for good play outside classic SR. Why not award Champion Mastery tokens as well then?