One important difference here is that people are free to discriminate on almost any grounds except a narrow set that have proven to be irrational and historically devastating. Race, gender, religion, and a few other things depending on jurisdiction.
The same rules apply to YouTube. If they had been arbitrarily banning the accounts of black people, they would have lost.
The wedding cake case in Oregon was much closer to what you describe.
The one in Colorado was more like the Youtube case. He offered to sell them a cake off the shelf, but refused to create a custom cake for something he didn't support.
It's not against the law to be a bad person. In fact, there's a famous quote from H.L. Mencken that "The trouble with fighting for human freedom is that one spends most of one's time defending scoundrels."
The legal question is whether or not you can be required to create, perform, or publish something against your will. So in that narrow sense, yes the two cases are isomorphic.
If you start trying to create a legal framework that grants rights based on who's a good person and who isn't, well... Then you have a long road in front of you, and as they say, it's "paved with good intentions."
That is true, but that's not what the Colorado guy was doing. (In the Oregon case, you're right, it's much more similar.)
The Colorado guy was closer to somebody who refuses to make a cake for MLK Day. Not making a cake to celebrate Martin Luther King does make you a pretty crappy person, but it's not quite the same thing as excluding a customer based on their race.
Similarly, a print shop could by that theory refuse to reproduce the resume of a black person on the grounds that they think black employment is against their religion. There's extensive (white) theological history supporting that position.
Of course, exactly none of this is the same thing as YouTube deciding not to run ads on some corporation's videos.
> If you start trying to create a legal framework that grants rights based on who's a good person and who isn't, well... Then you have a long road in front of you, and as they say, it's "paved with good intentions."
This is the absolute crux of the matter, and something that the current crop of puritans ignore.