The taskbar in Windows 11 is a downgrade in every conceivable way. I can look past having the icons be centered and grouped by default, as that is an option that can be configured. I can't get past not being able to at least make a double height taskbar. But the biggest frustration is that Windows 11 refuses to make ungrouped items have a static width. Moreover, the width of a taskbar item will depend on the title of the window. So when I have a browser open with multiple windows the taskbar will animate the taskbar item expanding or contracting based on the title of the page I am looking at. I, personally, find this incredibly distracting, especially considering how often one visits a different page or tab while browsing. While Windows 10 also changed the size of taskbar items, it only did that when opening a new window and the taskbar was full. Even so, it would resize all existing items to the same dimension.
This became nigh intolerable for me, but thankfully, I was given permission to install a third-party taskbar and start menu replacement called Start11. I would say it gives me about 95% of the functionality I wanted back. At home, I'm still running Windows 10.