Your point that other laws might (or might not) apply is a good one that people should note. "Trespass" is one. LinkedIn apparently alleged violation of the DMCA too. It chose not to press those issues in the appeal, so the opinion isn't direct authority regarding those other laws.
Where I disagreed is with your statement that the case "does not purport to provide any precedent on the legality of scraping." It does. It is persuasive precedent that the CFAA does not bar scraping publicly available data.
The first quote you mention ("I emphasize...") is from one judge's concurring opinion, not the court's full opinion. Further, the "little guidance" part of that quote doesn't mean that the opinion provides "little guidance" in general. The concurring judge was making the point that the parties shouldn't have delayed a full trial while waiting for the appeal. By "little guidance," he meant that the appeal provides "little guidance" to these particular parties about how a full-fledged trial will play out.
"Precedent" has a specific meaning here, in the context of legal cases:
> In common law legal systems, precedent is a principle or rule established in a previous legal case that is either binding on or persuasive for a court or other tribunal when deciding subsequent cases with similar issues or facts.[1][2][3] Common-law legal systems place great value on deciding cases according to consistent principled rules, so that similar facts will yield similar and predictable outcomes, and observance of precedent is the mechanism by which that goal is attained.
There was no principle or rule established here regarding the CFAA, thus no precedent that must be considered by other courts.
Courts generally try to restrict their rulings to the minimal needed to decide any particular case.
If the court had made a ruling, they would not make a point of qualifying all the statements about the CFAA the way they did.
The case did establish "principle[s]" that are "persuasive" for courts deciding subsequent cases. Put it this way: Say someone gets indicted for violating the CFAA by scraping a public site. You bet their attorneys will cite hiQ v. LinkedIn as persuasive precedent for dismissing the indictment. And the court, "when deciding" that case, absolutely will consider the Ninth Circuit's statement that it's "likely" that accessing "publicly available data will not constitute access without authorization under the CFAA."
Here's another point: When the Ninth Circuit decides a case, it chooses whether the decision is "published" or "unpublished." The Ninth Circuit rules expressly say that "unpublished" decisions are not precedent.
> Ninth Circuit Rule 36-3(a): "Not Precedent. Unpublished dispositions and orders of this Court are not precedent...."
Here, the Ninth Circuit chose to issue hiQ v. LinkedIn as a published case. If the Ninth Circuit wanted the case not to be precedent, it would not have done so, and easily could have made it "unpublished."
Where I disagreed is with your statement that the case "does not purport to provide any precedent on the legality of scraping." It does. It is persuasive precedent that the CFAA does not bar scraping publicly available data.
The first quote you mention ("I emphasize...") is from one judge's concurring opinion, not the court's full opinion. Further, the "little guidance" part of that quote doesn't mean that the opinion provides "little guidance" in general. The concurring judge was making the point that the parties shouldn't have delayed a full trial while waiting for the appeal. By "little guidance," he meant that the appeal provides "little guidance" to these particular parties about how a full-fledged trial will play out.