I don't even see it as increasing KPIs or sales. Unless it's sales as in selling the idea to the leadership.
A lot of it is trying to make it look visually and superficially impressive trying to apply the common hammers like whitespace, very little visible content at once as to not "overwhelm" the user and other rules to anything, and then trying to pretend whatever that is going to increase the sales by doing non-sensical user research, only listening to what proves their initial vision and then later trying to cherry-pick success metrics.
A/B test the new Settings panel:
If User spends more time in the Settings page -> We just increased engagement. They must really like the new Settings page and find that pleasurable to use. That's a win.
User spends less time in the Settings page -> We made it quicker to find and tweak the correct settings. That's amazing.
Either way, any change you make you can find wins. You could even keep going back and forth between two versions.
Also another common flaw I notice with some redesigns or things in general is that when the features, e.g. config settings were initially released, there was very thorough understanding and need for that feature and whoever put it there knew the technical implications and why it is needed, and they put it there in such a way that it's reasonably easy to use and makes sense with other things.
However when redesigning, you are going to be exposed to all those features and nuances at once. And you won't have a good understanding of everything at all and all the little details and implications. And you might want to start with some sort of feel, framework and design to handle all of that. But then you are going to approach those features from an aspect where you have to take the features and make them adapt to the design as opposed to considering what makes sense specifically for that feature. And you won't have good understanding of the features, so either you are reducing the scope a lot or also just implement features incorrectly or in a poor way, not working well together with some other features, etc.