The Xbox One System Update from May 2019 is already under development, bringing some minor improvements to your friends list, messages, and a list of games / applications.
Starting from the last one, the app list will now ignore "a", "an" and "the" in alphabetical order or grouping. It's kind of a change that makes me astonish that they no longer do that, as almost always makes for easier-to-use ads. Video games do not even have The to fight.
Changing the messages is pretty unexplained. There is a reasonable change: Incoming message requests from your friends are already sorted by priority, with non-friends requests placed in a separate category. But for some reason, Microsoft will destroy all bulk messages. You can save backups of messages for a limited time on Xbox.com, and messages with individual users are safe, but group messages are running. There is no clear justification for this change, as even if there are significant changes in group communications, Microsoft can be expected to cope with migrating messages from old to new.
The most interesting change, however, is that of the Friends list. Microsoft adds indicators to the name of every online friend to indicate whether they are playing console games using the Xbox app in Windows or using the Xbox app on a smartphone. This should make it easier for you to know the people you can invite for games, especially when the cross on the platform becomes more common. What's more, this highlights Microsoft's move to make Xbox a game brand independent of any particular hardware: you are still part of the Xbox ecosystem if you are on a PC or a mobile phone. Xbox is not hardware: Xbox plays games with friends wherever you are.
From the computer side, the Windows 10 Game Bar is renamed to the Xbox Game Bar, and the latest preview also includes the Looking for Group feature used to find people who play the game you want to play. Start searching for people to join your game, and you will be notified not only about the computer but also about the Xbox that someone has been found. This feature was previously available in Windows on Xbox app, but placing it on the Game Bar makes it faster and easier to use.
All this seems to be that Microsoft blurs the lines between Xbox, PC and Mobile gaming, and we can only expect these lines to become even more unclear in the future. The Xcloud gaming service further undermines these platform differences while premium experience will be available on the console or on a high-end computer, streaming games should make many games that can be played on virtually any hardware. The last missing part will certainly be the ability to play Xbox games on a PC. There are already signs that Microsoft is working on this issue, but such a change will further enhance this shift in the focus of game console hardware wherever you are.