I'm curious about what was the inspiration for this overhaul (was it money?) but I feel really happy about it.
The new lore is a product of lack of creativity at making quality content within self-imposed limits of a setting.
The old lore was torn down, because Riot couldn't be assed to work within bounds they set for themselves, thus we got no bounds left and any "champion" can be created. The result is a bunch of unrelated stories floating in a void.
They couldn't even been assed to properly deal with the old lore.
No. They took the easiest way out and it's the way of writers who are simply incompetent - a complete retcon.
The end result is a world with no limits and only a bare minimum of rules.
That in turn kills the suspension of disbelief, all the drama a story could have and leads to balance issues down the road.
Hell, it's already there.
We have a cosmic semi-ethereal dragon that's the size of a solar system that can destroy and create stars with a finger-snap controlled by space-faring(?) parasites that can take complete control of any person they deem necessary.
Why should I care about some guy making a journal about a fox slut in a backwater village if it all can be obliterated with a sneeze?
If you look at stories on a case by case basis they are good, but as a part of a setting it's all low quality garbage, that will never become good.
Not until it gets completely retconned again.