Perhaps the most salient feature of the Mueller Report is the calcification of the notion the president is above the law.
There is only one rebuttal which I will demonstrate is fallacious. You will say Congress can impeach and convict a president, then he may be indicted and tried. But please notice how you are arguing my claim.
First, until a president is convicted of impeachment charges, he is still the president and still not accountable legally i.e. he is above the law. Second, should a president be convicted of impeachment proceedings, and then be indicted, he would no longer be a president and would therefore be an ordinary citizen.
I do not think the Founders had that in mind.