It’s somewhat bizarre to me that the settings menu isn’t just a reskinned control panel that either launches the new or old items depending on what they’ve finished so far.
I can’t imagine what they’ve done is easier than rewriting control panel items in full one by one.
You can do a halfway decent job of modernizing just by having an “advanced” toggle that shows the more arcane/less used settings.
I understand the desire to race towards a minimum viable product and get the core functionality into the glossy new thing, but they already had a minimum viable product in the control panel.
One of the uses of notepad was also that it’s installed by default, and was a place you could be assured wouldn’t mess with your text. No formatting, no weird characters you didn’t ask for.
Notepad++ is great, but you can’t be assured it’s installed on any arbitrary Windows machine.