Rob, I think ACA and Collins are significantly different. ACA’s overall mandate (pardon the term) is universal healthcare while also allowing individuals to choose which healthcare they want. A noble cause, one both Republicans and Democrats agree on, they only disagree on the how, and in fact they aren’t that far apart on the how, just sound bite politics.
GSE conservatorship is the executive branch running amok, imposing their will, and nationalizing companies.
IMO, the old cliche of “intent is 9/10ths of the law” will hold true here. Sweeping all profits to gov coffers to be used arbitrarily vs attempting to provide affordable healthcare for all. A very large difference that won’t be lost on the majority of the court.