Hitting options in the guide is laggy to not usable

Well it's officially no longer a Preview Program issue.

I completely unenrolled from the Preview Program and performed yet another factory reset. Everything worked perfectly for a couple of days. I hear the "chime" noise when I hold the guide button, I can smoothly go between menus, everything worked great. Until
I started reinstalling all my games and Rock Band 4 DLC. Particularly while the Rock Band 4 DLC was installing (several hundred files, I should say) and I'm getting all the notifications about each song being ready to play after they're installed, I noticed
the lag came back. It's taking a good 30-45 seconds for my "What do you want to do?" menu to pop up and the "chime" noise that goes along with it is gone. Menus are laggy. I press down several times in the guide to get to an option at the bottom of the screen
and it'll freeze for a second, before jumping down there suddenly.

I'm really at a loss here. The console seems to work fine until I start installing things. And yet, everything is installed to my external, and I have the same problem when my external is unplugged from it.

Since you're a member of the Xbox One preview program, please be sure to report any issues you come across using the Feedback app and then post on our Preview
Program forums for further assistance from the proper folks.

Thanks!

Heeeey. Good news!

There is a new feature on your Xbox One. You can now do a factory reset BUT
only wipe the system partition.

That's right, if you go to Settings -> All Settings -> System -> Console Info -> Reset

You will now have 2 options (besides cancel)

1. Reset and remove everything

2. Reset and keep my games and apps

When you choose the second option, your system will wipe the system partition and reinstall it. When it boots back up, you'll be asked the normal things, what's your time zone, what's your favorite color, what's your name and password. But then you get
in, and your profile and games and apps are still there.

This can fix a TON of lag issues, because it can clear up all kinds of nasty partial files and overflowing cache files. Personally, I think I'm going to make it part of my semi-annual upkeep.

In your case, I would recommend uninstalling netflix, do a reset keeping your games and apps, get back in and reinstall it. Once you do that, I bet you'll be just gravy. But let me know.

You might have to factory reset. You can save it all to an external had drive so you don't have to redownload.

Does this happen with other streaming apps?

It doesn't happen with other apps... And that's why I'm confused because it usually fixes itself after some time but I am just tired of waiting for it.