It's a fair request, but there are so many areas of the OS that have small decisions like this, if there were a setting for all of them... Settings.app is already a little burdened under its own weight (though the search bar has helped a bit).

The set-up process for a new iPhone is also reaching crazy levels, with so many decisions for new users to make.

Don't really know what the solution to this is to be honest -- Linux-style config files maybe? :P

You don't deserve the downvotes but, honestly, it's a pretty techie view of the world in which everything everywhere should have a zillion customizable settings to tweak and tune every aspect of interactions/user experience. I sometimes appreciate this myself. But, most of the time, I overall prefer that someone has created a streamlined experience and made decisions for me.

I don't pay an excessive premium to Apple to make poor decisions for me. I could avoid touch bar and USB C by just not buying their new products. I can't avoid poor decisions pushed on me through updates for products I've already paid for.

Which is why having choice of products to buy is a great thing. By all means buy platforms that give you a greater degree of customization if that's your preference. But understand that different people have different priorities and one path isn't inherently better than the other.

The phone will automatically download the update, but not install it. To delete it, go to settings->general->storage and icloud usage->Manage Storage (there are two buttons that say this, click the top one). If the update downloaded, it should be there. Tap on it and click delete.

The other thing you can do is install a tvOS beta configuration profile. This will make your phone look for tvOS updates rather than iOS updates, which it will not install because they're not for ios. I won't post a link here, but it should be fairly straightforward to find.