League of Legends is a game made by a small start-up that unexpectedly became a major corporation in the industry. Its original design was never really intended to be perfectly workable in the long-term, nor viable across a player pool of literal millions, and it shows. Much of Riot's work thus far in more recent seasons has been reworking legacy systems, features and champions to bring them up to better standards of design, which is why so many resources are dedicated to reworking existing content, rather than producing new features, and why the big milestones each year now revolve around roster updates, rather than new champions, game modes, in-game world events, etc.
The issue with many of these updates, however, is that while Riot's been trying to bring the game up to modern design standards, what counts as a "modern design standard" changes really quickly over time, as the devs are discovering pretty much at the same time as us players how they need to change their approach to design. Because of this, updates that seemed sound at the time now need touch-ups, or sometimes entirely new directions. On top of this, most of these updates are given a limited scope that somewhat detracts from the real problem, and it is my personal belief that many of League's fundamental systems are not viable in the long-term: systems like runes, masteries are even items are not conducive to true customization or freedom of choice, and even hinder design and balance by making it significantly more complicated and prone to abuse. Attempts to update these have been mostly the equivalent of adding a fresh coat of paint to a crumbling wall, so even if each update feels somewhat good, none of them really address the fundamental issues at hand, which simply leads to more updates along the way.
One of the reasons why it's difficult to make sweeping changes to these systems, though, beyond just scope limitations, is that any kind of hypothetical League 2.0 update, or any other major set of changes, is likely to significantly upset the playerbase, who'd find themselves losing many features they got attached to over time. Getting rid of runes, for example, is likely to piss off players who have invested time, effort and IP into filling up and curating their pages, in spite of how boring the system is overall. Similarly, getting rid of even bigger systems like masteries and itemization, and replacing them with something more modern, would risk turning a lot of players off simply because they'd end up having to deal with something completely unfamiliar as a new core feature. To some extent, Riot is trapped by their early choices, and while it's still possible for them to overhaul their game, doing so would be extremely costly and risky, no matter its long-term benefits.
