The other way of looking at this is that conservative States can't boot Biden from the ballot either.
And you could bet your ass that if the ruling went the other way Biden would be off the ballot in every red state too. And that would be a much bigger mess than Trump being on all the ballots.
Except justifying Biden as having committed insurrection is a hell of a lot harder than Trump, who was found to have committed insurrection as a matter of fact.
It protects Biden, sure, but from an extremely remote possibility, instead of an imminent one.
In order to legally classify Biden as an insurrectionist, they'd have to come up with hare-brained legal gymnastics and then they'd need, like, a majority in the supreme court to rubber-stamp their...
Eh, for what it's worth, SCOTUS has said it's Congress's job to determine that, because the self-executing portion of the Constitution apparently needs an executor. 🙃
They've been setting that up for weeks, though. They started calling the migrant crisis in the Southern border an "invasion". You can bet that if the Court held up the Colorado ruling, we would have a ruling in short order in Texas (possibly AZ too) that Biden was ineligible for directly causing an invasion. No matter how incorrect that take is.
It's not about that. They would just make something up and say that's why they're doing it. "Something something Hunter Biden" therefore Biden is off the ballot.