In the same way, some icons (depending on the app) they may no longer appear in the taskbar after upgrading to Windows 11 and some apps can no longer customize areas of the taskbar, according to Microsoft docs.
Also in preview builds Microsoft is experimenting with moving all Taskbar context menu options (when right-clicking on Windows 10) in the Settings app. This move would further simplify the experience and reduce clutter, but it could be a problem for users who haven't activated Windows. In the non-activated copy of Windows, you cannot access the customization options.
In any case, Microsoft has confirmed to be listening to feedback of Windows Insiders, or those who are already testing the preview betas. So it is likely that some of these missing features will be restored in the final OS build, but there is no guarantee.
Windows 11 is currently in the final stages of development and will begin to be distributed to eligible consumers before the end of the year. For those with unsupported devices, Microsoft says it will continue to support Windows 10 with version 21H2 and other updates, but the big changes will remain exclusive to the new operating system.
The Windows 11 taskbar is worse than the current one, but it will get better