Guess some myths never die.
Darvond: It's the truth. Maybe they'll fix it for the probably upcoming Magic Mouse 3, unless Apple is in full headless chicken mode now.
The MM can be configured for secondary clicks. Every Apple mouse since 2005 can. And it has gestures, touch scrolling and other stuff. Not a fan of it, but its far from being a one button mouse.
Actually Mac OS has had multi button mice support for 20 yrs now, no one was forced to use the (mostly silly) Apple mice. Some multi button mice worked even before that (over ADB, but with vendor-made drivers).
@ OP id just get a cheap USB mouse (or a decent one since you might get used to it ;), any will do for basic functions (so, right, left, middle click and back/forward buttons too usually), "gaming" mice with more buttons need dedicated drivers though (or some work to setup with third party software), so Logitech or MS are usually the best choice.