There were serving a search warrant, not an arrest warrant.
That’s why a simple polite knock at the door was all that was needed. And sounds like they were searching for illegal guns of some such... he can’t flush those. There was no need to hit with an assault force, or to do it at 6am.
That is reserved for when they guy has a criminal background that indicates a violent path and probable violent resistance. If he responds to the door in a psycho angry way, back off and THEN go the SWAT route with time on your side.
This was amateur and unprofessional.