The key drop system makes losing feel like a punishment
Losing games is already no fun. You get less IP, you may have lost LP, you probably had to slog through several minutes of of your team bickering and blaming each other for everything up to and including why the enemy jungler got fed and why their spouses want a divorce.
With the regressive drop rate of keys, it feels like every loss is even a bigger waste of time. Past the first key every month, the decreased drop rate makes it feel like keys just don't drop, and losing just slows that grind.
Can we have a system that rewards playing consistently, rather than winning consistently? Make it so losses roll for keys too, and getting a successful roll on a loss means we're guaranteed a drop on our next win. Losing already feels like a punishment, why make it actively punish you with less rewards as well?