Dams don't prevent floods, they just move them from one place to another. When a river such as the (Texas) Colorado has multiple dams along its length, each of the dam managers have to coordinate with each other on a strategy that minimizes damage along the entire length of the river. This means that the best strategy for one location might cause much more damage to others.
From my perspective, along the Guadalupe, the river which experiences more flooding than any other in the US, I think they do a pretty good job.
Then you should know LCRA operates all the dams along the lake chain. They aren’t run by different organizations that must coordinate with each other. Open the upper one, then the second one, then the third and on down. The October rain was upstream so there was no problem whatsoever opening any dam downstream. They had several days warning and failed to do anything but pick the lint from their belly buttons.
I’ve lived on LBJ lake most of my life and have seen first hand how LCRA screws up everything they touch. I have called them to report a level problem and they tell me my eyes are lying. No, they sit behind their computers two hours away and don’t have a bleepin’ idea what’s going on. They also claim no flooding can happen at my house because water can’t turn that direction and flow upstream. HAHAHAHAHAHAHAHAHAHAHA! Water will turn every direction to find it’s level, yet they can’t figure out that very simple fact.