This solved the problem for me.
https://superuser.com/questions/1460439/icons-automatically-pinned-to-taskbar-after-every-reboot-in-windows-10
C:\Users(youruserhere)\AppData\Local\Microsoft\Windows\Shell\LayoutModification.xml
Looking for this line
CustomTaskbarLayoutCollection PinListPlacement="Replace"
I did a ctrl+f and searched "custom"
Found the lines with xbox app and dragon center app
Removed them and saved xml
Rebooted and they didnt show back up.
I saw this in the LayoutModification.xml file
<CustomTaskbarLayoutCollection>
<defaultlayout:TaskbarLayout>
<taskbar:TaskbarPinList>
<taskbar:UWA AppUserModelID="9426MICRO-STARINTERNATION.DragonCenter_kzh8wxbdkxb8p!App" />
<taskbar:UWA AppUserModelID="9426MICRO-STARINTERNATION.CreatorCenter_kzh8wxbdkxb8p!App" />
<taskbar:UWA AppUserModelID="Microsoft.GamingApp_8wekyb3d8bbwe!Microsoft.Xbox.App" />
</taskbar:TaskbarPinList>
</defaultlayout:TaskbarLayout>
</CustomTaskbarLayoutCollection>
removed
<taskbar:UWA AppUserModelID="9426MICRO-STARINTERNATION.DragonCenter_kzh8wxbdkxb8p!App" />
and
<taskbar:UWA AppUserModelID="Microsoft.GamingApp_8wekyb3d8bbwe!Microsoft.Xbox.App" />
this fixed the re-pin taskbar problem with the dragon center and xbox app store.
The OS should honor the unpin command permanently and not require hand editing an XML file buried in the user AppData folder to permanently unpin an app. I wonder why it is so difficult to unpin these specific two apps from the taskbar... oh wait money, money
is why. Having to do this Internet search and then hand edit of a file to remove these apps (that I never pinned) ensures I never use either of these apps unless I am forced to. It also indicates to me that no one would ever use either of these apps unless
they were obnoxiously unremovable from the viewing area of the computer thus in front of the user without their consent continuously... like an advertisement. Surprised Edge wasn't also perma-pinned to the taskbar.