The gallery doesn't work anymore on xbox one.

I have the same issue, I can't find a way to get the gallery back, I'm not sure why it's missing. I can only access my library and what I've previously saved and downloaded.

I think I've fixed it. Go on Game option.

Then to other

Click on online social features and tick it on. There also should be a link to EA account, click link and follow the steps. My game reloaded and the gallery is now back along with enabling the nature's  calling event. Not sure which one fixed it so I included both

Some of us do not have the "Online social features" box. See above screenshot from OP at the top of the post. Glad it worked for you!

The game option is in the settings not the library. I'll include some photos. Though the link to EA account has disappeared now that I signed in.