The balance and design teams loves to get cute and cause tons of collateral damage in the process
This seems to basically be the root of all of the problems people have with the balance team. Every time you guys are presented with an extremely simple problem that can be directly addressed, instead of doing that you guys try to go full Apple and remove the metaphorical goddamn headphone jack because you wanna take a needlessly "brave" and/or "innovative" approach to everything. When the community is thirsty, instead of giving us the glass of water we asked for, you guys would rather use cloud seeding and then tell us to go outside and catch rainwater with our mouths in a few weeks.
When there's something problematic in the game like a certain skill, rune, or item being overpowered in the game, I feel like you have some misguided arrogance that makes you exhaust all other options before taking the most obvious approach. This is where the "nerf the champion, then nerf the item, then never revert the champion" meme comes from.
And then we have shit like some of the most recent hated reworks, runes, and new champions. You just can't just reinvent the wheel. You have to reinvent the wheel, the axle, the motor, and the bearings. Then you have hastily chuck all of that unnecessary work into a single abomination because tuning is the boring part.
The most recent issue I have is the Sion nerfs. His E is obnoxious, oppressive, and blatantly overpowered. So instead of not making it scale so hard or decreasing the efficacy of spamming it, Riot decided to nerf his Q at lower ranks with the theory that it would encourage consideration towards maxing Q instead, indirectly hitting an already niche AD Sion hard in the process. I'm betting right now that this will only just make Sion E maxers more passive and reliant on E, since they can't also get more aggressive with Q. Targeting a champion's weaknesses instead of their toxic strengths often just leads to them avoiding those weaknesses even more and leaning more heavily on those toxic strengths. Sooner or later I'm almost certain E is going to get nerfed for reals, and this Q nerf wont be reverted or readdressed.