Spicer's statements as press secretary represent neither a legal precedent nor necessarily the opinion of the Justice Department, though. I know you didn't specify "legal precedent", but that's the only precedent that would've mattered here. This is why this case had to be sorted out in the courts.

On the topic of Musk, the SEC has protocols that need to be followed. Even if Musk blocked 0 people, I'm sure he'd be under investigation.