One of my long-standing peeves with all operating systems is ignoring the left-handed mouse user. A left-handed mouse is the term used for swapping the primary and secondary mouse buttons.
While all operating systems support left-handed mice — swapping the buttons, none of them are designed to ask users whether they want to use that option.
Linux login managers all are right-hand mouse centric. When a left-hand mouse user logs out and returns to the login manager, the user must mentally and physically swap the buttons to the use login manager.
As login managers do not use context menus, they should be designed to be button agnostic. Both buttons should work as a primary button.
One of the options never included in a distro installer is asking to swap the mouse buttons.
One of the options never included the first time a user launches a new desktop is asking whether the user wants to swap the mouse buttons.
While I expect more from Linux developers, to my knowledge none of the proprietary operating systems handle this well either.
Developers, please start embracing left-hand mouse users.