An editor is an editor after all Isn't it?

Just re-starting on Lisp after a gap of 18 years. Worked on AutoLISP, now moving to Common-Lisp. Never used Emacs before, but see it being recommended by CL grey-beards. Is Emacs mandatory for CL programming? If yes, why? Shouldn't Vim with syntax-highlighting and indentation rules be good enough?