A person who opposes optionality or the provision of choices; someone who advocates against having multiple options available.
From anti- + optionist (from option + -ist). This is an extremely rare term, likely a neologism, as it contradicts modern consumer culture's emphasis on choice.
An 'antioptionist' would be incredibly unpopular in modern capitalism—we're so obsessed with choice (50 kinds of cereal, infinite streaming options) that someone arguing we'd be happier with fewer choices sounds almost revolutionary.
Complete word intelligence in one call. Free tier — 50 lookups/day.