Perhaps, after decades of application bugs caused by developers not properly accounting for taskbar position and size, random ordinary users being distressed by accident'ly moving or resizing the taskbar and unable to get it back (leaving aside savvy users), Microsoft have given up? I seem to recall various articles on this over the years, including on Raymond Chen's "The Old New Thing".
Mild example: https://devblogs.microsoft.com/oldnewthing/20040513-00/?p=39...