My only transparent tile is "my games and apps".

The transparent tiles should be more transparent like Doc mentioned, other than though its pretty meh in my humbled opinion

I'm having the same issue and reported it along with a screenshot. The recently used games and apps are still solid even after selecting mostly transparent in the options menu. All other tiles prior to the latest update are transparent

I spoke to 2 ambassadors. one said the change came with the system update. directed me to change my tile transparency, then exited the session before I could try. I see my tile transparency is set to solid, but it will not let me change it. My buddy's is
set to solid as well, and his tiles still show the images, and not solid color as mine do.

One tile says "ms sourceDESC.APPNAME" or something. I didn't get that in the picture.

I hope this doesn't lead to further system errors.

I've got the transparent tiles and they look good. Best to set the tile colour to something like the grey-ish one, they become more transparent then.

There is already the concept of transparent tiles implemented by the Xbox One. It may not be what you envisioned and you may have better suggestion for future updates to this feature. Head over to the Feedback forums and add your own take on the tile transparency
or find the idea that best describes what changes you would like to see made to this feature. If you find an idea similar to what you want out of the feature you can just add your own comments to the idea to help further explain your vision. Cheers!

Adjust tile transparency
Adjusting the tile transparency allows you to better view your custom background through the tiles on the screen.

Note You cannot change tile transparency if your background is set to a solid color.

To adjust your background:

1. 1. Scroll left on the Home screen to open the guide.
2. 2. Select Settings.
3. 3. Select All Settings.
4. 4. Select Personalization, and then in the right pane, select My color & background.
5. 5. Select Tile transparency on the My color & background page.
6. 6. Choose the transparency that you prefer (Solid, Mostly solid, Partly transparent, or Mostly transparent).