It’s all interpretation though, isn’t it? Unsurprisingly, the Constitution has very little say on the topic of health insurance. How the content of the document gets applied to modern contexts is a matter of enormous debate, in a lot of contexts “unconstitutional” is a moving target.

It used to be the case that anything that the Constitution didn't allow the government to do was considered not allowed. Too bad now it's the opposite - anything the Constitution doesn't explicitly prohibit it to do, it feels free to. And anything it does prohibit - like regulating speech - it does anyway, in a roundabout way. But at least we got all the problems they promised us to solve this way, actually solved, right?

whether or not something is found constitutional just depends on the prudence of the bench. Segregated schools were found constitutional under the same constitution that later found them not to be. The Supreme Court overrules itself all the time; the march of progress is slow: https://www.grunge.com/895625/the-supreme-court-has-overrule...