Gray homescreen with nothing appearing. But can access the Guide

i am having this issue too! also all the boxes on my homescreen are just gray or green (apart from the games) all the apps like netflix, twitch, youtube, upload studio, are all just blank gray or green boxes instead of their logos!

Some options appear grayed out if you are using an accessory that takes advantage of the audio mixer functionality or if you are using hardware where audio adjustments are made on the hardware itself (for example, a Chatpad or some third-party headsets).

Check if there is no accessory that is using the audio mixer function and that is why they appear grayed out.

Tell me from which device are you using the headphones? Depending on that, we can guide you through some possible solutions.

Information Source (Credits): https://support.xbox.com/help/hardware-network/getting-started-set-up/using-the-guide

I hope everything is resolved, I will be attentive to your response.

Are you just sitting at the homescreen? While playing a game the logo doesnt appear. There is no way to turn the logo off,so it would be best to avoid sitting at the homescreen for an extended period of time

OK after pressing the Xbox button to bring the guide up and without pressing any other button on the controller try pressing the A button twice and the console should then return to the homescreen. If the console does return to the homescreen then the console
is behaving how it should.

That's odd, Lost - my guide never opens up unless I press X while on the homescreen... Weird.