If I recall, last year almost 30 percent of players were in Bronze and another 30ish percent in Silver. This year there are only 17% players in Bronze, and 2% in Iron. How is this drastic change possible? Adding more tiers to climb up realistically should prevent players from climbing higher, not make it so there are more players at Gold rank than there ever has been before. Also how does Iron only have 2% of the player base when last year almost 30% of the players in the game were Bronze tier?
There are many red flags all over the place here, screaming that something is up with the matchmaking. Statistically what is happening is unrealistic and cannot be explained outside of undocumented adjustments to matchmaking by Riot. A lack of hard reset could be one part of the issue, but even then it's not a full explanation since every season you start lower than you ranked the previous season. Realistically there should be an equal amount of players in Iron and Bronze as there were last year, or even more players in Iron and less in Bronze. There should be a drastically lower amount of players in Silver and Gold. Instead we see the opposite, where there are tons more players in Silver and Gold, and lower tier players (Iron, Bronze) are almost non-existent.