That trend of blurred lines has been going on for quite a while. Iirc a big callout of the 9/11 commission report was lack of communication between the FBI and the CIA. Even on the local side increasingly it seems every major crime gets a mixture of various federal, state and local law enforcement response.
A notable case was the Uvalde school massacre, which only ended when a border patrol tactical team (believe from the BORTAC group you mentioned) took over from dithering local forces. This was a major example, but interagency collaboration has also become routine in far less dire circumstances.
The militarization and blurred lines have thus become a feature not a bug. And it won't be reformed simply by having the current administration fade into the rearview mirror. It would be beneficial I think though if current excesses led to a more holistic introspection and reform, but we'll see.
The CIA and FBI had been deliberately separated, after the Church Commission found many, many abuses.
The Patriot Act removed and lowered many of the barriers. And now we're back to what the Church Commission found.