Some people really undervalue the idea of having workers not feel pressured and having some privacy. You might get 10-20% more productivity out of them in the short term, but it raises stress a ton, destroys their mental health, and you probably lose that extra efficiency in burn out and depressed workers anyways, I er the long term it taints everything the company touches. It destroys morale, makes every interaction with a customer slightly worse, makes every work they do worse.

Open layouts are terrible, humans are not designed to exist in an environment where they are constantly monitored. People have to take breaks sometimes, people have bad days sometimes. The way you deal with this from a management perspective is you look at their average efficiency over longer periods of time and judge their worth based on that, but while preserving their humanity and autonomy. Humans are not meant to be drones, and good workers come from having happy and healthy workers.