My theory in to how balance works with riot games. NOT a complaint/troll thread.
Non of this is definitive fact as I haven't been around in the game for long enough to say from experience and my time playing with a proper grasp of the meta and proper understanding of the game is even shorter.
From what I can tell the difference between riot games balance decisions way back when and their decisions now is how riot treated their game and the meta. That sounds like a vague statement but what I mean is this: From what I can gather Riot essentially let the community decide the direction of the meta in the older league of legends while tweaking balance and making small additions which lead to less spiked power across the board with champions and more of an even and comparable power level between all champions in the game.
Basically the community would shape the meta for themselves while riot balanced around that fact without trying to impact the game from their end too much and instead focused on giving the community what they needed to further shape the game for themselves.
Around season 5 it seemed like riot changed their way of thinking and instead went on the attack by shaping the meta themselves with large amounts of mechanics and massive balance changes/tweaks loaded into almost every patch basically forcing the meta to change based on where they wanted it to go.
Again this is mainly just theory based on what I know of how the game has worked in the past and how it works now.
I started in mid season 4, started ranked in mid season 5, and now I'm here.