Flat mana and health regen is outdated, please update those kind of runes.

I don't know how far back that was but there was a point when health and mana regen was reworked from being a flat value to being a percentage of your base mana/HP. This was really great and made regen finally scale much better into the late game and generally just viable again where the flat regen would just become useless over time.

Now what I always wondered about is why items got updated in that way but runes did not. It just doesn't make a lot of sense and I think we all can agree on flat regen runes being pretty much useless atm. I mean if flat pen gets updated to lethality then why wouldn't flat regen get updated to percent base HP/mana regen?