More productivity means that you produce more wealth. If you are less productive you are worth less. (Stop saying the rich take the wealth, that is what unions claim they are preventing).
It is a logical fallacy to read what I wrong as saying there is something wrong with not wanting to go onto management . I said there is something wrong with stopping someone who does want to go into management. Those are very different things.
If you want to stay where you are, I have no problem with that. However if you turn your wish to not improve into holding back someone else who does that is wrong ' (improve here as defined by the other person's values and what they think would improve them)