Lots of loyalists have replaced people there. It's for sure incompetence.

There are hundreds of thousands of documents being reviewed by probably a thousand or more FBI agents. There is zero chance they are all loyalists.

Indeed, incompetence is basically guaranteed if the organization selects for allegiance rather than competence. But I prefer to think that at least part of this was malicious compliance, because that suggests that at least some people at the FBI still have their soul.