The problem isn't where human resources are spent, its where monetary resources are spent.
Riot is paying people to work on these things, and not paying enough people to work on gameplay, the client, the engine, etc.
And Riot already has far more funding than 99.999% of games will ever get, while doing less than many. Saying they need to nickel and time everyone even more for the game to stop its tailspin isn't really helpful.
Riot has had the money to make improvements that needed to happen 7+ years ago for nearly a decade. Its silly to think money at this point is the reason why things don't happen.
Its intentional that the game isn't actively improving anymore because it makes money whether it does or not.
(Speaking from honest personal view because I’m not the expert on this) The problem with being one of the largest, also mean you are one of the most expensive to just run. It’s not often people gets to see behind the scene costs. I worked on Client, Skins and Champs side previously and it does surprise me where hidden costs are 🤔 Not all regions are equal in terms of profit vs cost.