And that is the case they are meant to be deciding.
I don't think Trump will get precisely the immunity he wishes for. But it is plain the conservatives on SCOTUS wish to use this case to redraw the protections and powers of the presidency. So they may completely undermine the case against Trump and his insurrectionary behaviour.
Since they've already made a bloody great mess of the big questions they've answered, you'd think they might think maybe they aren't the visionaries they think they are. And to be a bit more humble in their approach.
Unfortunately, it's the nature of rogues that they don't really care that much. They are going to try to redraw the way it all works, regardless of the fact that their job is merely to interpret the constitution in a sensible way. They are installed, not elected, so don't have that democratic legitimacy. Indeed, McConnell has created a situation that is utterly divisive by imposing Republican justices and unbalancing the court.