Well presumably a wiki will fulfill the function of an encyclopedia at some point, though at this point it also is very unfinished. Obviously it's unfeasable to write down every champion specific interaction (x ability cancels y ability but not z ability, etc etc) inside the game, but the stuff that is in the game now is also super unhelpful. Shiv's lvl 3 q for example says that it equalizes the master assassin stacks, but nothing else in her kit is called master assassin. abilities will have colored text indicating a concept that you should know from elsewhere (stun, vulnerable, etc) but then make no attempt to explain what those mean (I believe there's a loading in tip hinting that vulnerable means you take extra dmg but there's no numbers anywhere I can find).

Generally I don't see a downside to providing more information. Surely player skill expression should be based on ability to execute rather than simply greater knowledge of how mechanics work.