They absolutely do. If you're tech savvy, they're optional. If you're not, or not interested in learning this stuff, they're required.

You can absolutely be tech savvy and prefer the ease of use of Elementary OS's default options. But the converse is not true. You cannot be uninterested in tech and have a good experience running i3 on Arch Linux.

Not exactly, but it takes tech savviness to put together a nice UI that is easy to use.