well the players from earlier seasons of league were kinda told this by content creators / streams etc
to be able to play at least 2 champs in every role if you dont get your main... cuz you know bans/pick order etc and being forced to fill an off role. (people wanna act like filling in rank is new LMAO )
and dont jump into rank right when you reach level 30 ( if a new player ) because 100-150ish games isnt truly enough to know this game
i remember back in season 3 watching a guide on rank from a high elo player saying dont even try rank til you have at least 2 basic rune pages AD and AP and at least 300 normal wins and then you were ready for bronze
but now people just wanna play hundreds of games of rank to try to climb elo with out learning this and how to play or play against most champs
i think riot kinda took notion to this and part of the reason my the champ mastery system was put in place so it would get people to try to get mastery on multiple of champs to improve the game knowledge across the board and also a way to get people to play more games ...