Who polices the police?
The FBI is institutionally incapable of cleaning out their house and ensuring transparency and integrity.
If the DOJ IG had more power, perhaps the FBI would pay attention. But Wray, even if he wants to change the culture, is up against a corrupt organizational culture that has for generations been covering up its misdeeds. The culture of the FBI is to protect the "thin blue line" even if the FBI employees are corrupt and evil (as in Strzok/Page/McCabe etc).
https://twitter.com/TomFitton/status/1212413757315538944