Still is to some extent, and a lot of people just cannot pull them off, so stigma or no they do look worse just like if they were wearing crappier clothes (I'm this way, a bit—hard to find glasses that look at least OK on me rather than awful).
Perhaps better to say that there's no stigma to finding out that someone wears contacts or has had LASIK surgery. Those match the intuition of ADHD as something that's a personal/"invisible" problem, with a personal/"invisible" treatment.
Ah, yes, that's true. The social benefit to having 20/20 vision naturally instead of through surgery or wearing contacts is very low, even if people know about the contacts or surgery.
So was a number of other perceived biological outliers, including left handedness and melanin content. Although not perfect, as society progresses, these outliers are accepted more over time.