Perhaps they've read a summary of the decision that they trust? Also, the decision is based on a single-paragraph long part of the constitution. I tentatively

Perhaps they've read a summary of the decision that they trust? Also, the decision is based on a single-paragraph long part of the constitution. I tentatively disagree with the decision*, consider this hypothetical: a one-thousand page long decision that ruled the government was allowed to censor all anti-war speech, based on the 1st Amendment. It would be bizarre to expect only people that read through the whole thousand pages to comment on such an on-it's-face misguided decision. *But I don't consider it entirely unreasonable, and I think the law behind it addresses a very real problem that we shouldn't ignore by sticking our heads in the sand and yelling "1st amendment".