So just to spell something out, the inevitable result of a president actually using the power SCOTUS just gave him is either dictatorship, civil war, or both. Democrats don't want either and therefore can't use that power the way that Trump will if reelected.
Yes, it appears to be the case that SCOTUS just said Biden could have Trump (and any other Republican politician he wants) killed. If he did that large-scale political violence would be the result.