In probably pouring gas on a fire here, but f*ck it.
I see a flood of complaints on two issues, the runes (even a year later) and damage creep. I have am idea on why this is happening, and why is not being reverted.
Many people seem to have less and less of an attention span every day. There's more demand for quick hitting, easilly accessible, in and out kind of games. Given that people naturally lose interest in things over time a company has to put a significant effort into finding new fans, not just pleasing current ones.
More damage means more action and shorter games.
The narrowness that people complain about with the new runes translates to easier set up for incoming players.
My hope at present is that nexus blitz, or a similar mode will be immensely popular and fill the quick hitting action packed role so summoner's rift can gain back some of it's old strategy and pacing. But from a business standpoint if they stop trying to change with the public, or even more so if they actually were to revert things, you might as well do like HOTS and pull all the developers and leave the game in stasis, because it would very likely reduce the inflow of new players.