How do you remove the "Tab Manager" icon from the browser. It serves no purpose to me other than to take up space and piss me off.
"When modifying existing UI, never add elements without giving the user the option to remove them" - One of the Principals of UX.
This can also be summed up with "People don't like change", "You can't please everyone, so don't force your changes on them", and "If it ain't broke, don't fix it."