The legacy of Mueller is that if you do diligent methodical careful work on a damning report, trusting to our institutions to do the right thing, damned liars will just tell damned lies about your work and the lies will stand, because institutions won't confront power and nobody does the reading.
The Mueller report should have been not only the end of Trump but the end of the Republican Party from rump to snout, and it's only one of maybe 1000 things that should have been that. What's needed now is a confrontation with uncomfortable truth and a meaningful lasting reckoning and reformation.