The longer that Trump,Barr, and the Republican enablers in Congress keep up the combination of stonewalling and doing a full-court press counterattack based on the idea that Trump was the victim of a conspiracy, the stronger that combination becomes. The Mueller report, even in redacted form, details obvious crimes and grounds for impeachment. Acting like this isn't true creates the impression that it isn't true, which makes the stonewalling/conspiracy press even more effective. What Josh used to call "bitch slap" politics really plays out in this.
I'm really worried that we're going to look back at this as the lost opportunity that could have prevented them from manufacturing a consensus that Trump was vindicated by the report, when it actually shows the opposite.