The image on the right is how the settings app look on macOS 12. On macOS 13 (2022) it was changed to look more to the one on the left, with all the sections selectable in a sidebar and a smaller window. Many users have complained about it, saying that it sacrificed function for form and is part of making macOS more like iOS by mindlessly copying phone UIs onto computers which it isn’t meant for. I think its alright, not terrible. And it’s the norm with settings apps looking like that in Windows, KDE, Gnome, and some other DEs.
Left, but in reality I’m only ever using the search bar. Further, if the OS has a good universal search (like command space on Mac) I might not even be using the search bar in the settings app directly. Search bars in settings are a blessing and I’m so glad they’ve become the norm.