I don't see that at all, actually I've state this point to the contrary.
He drew the gun front and center as he walked towards the door, and had a mask and gloves on a temperate night leaving all doubt of a ruse, rather "exposing himself" for intimidation.
Most pros would not expose themselves until they got in (both makes it easier to ruse your way in, and prevents a random person on the outside spotting you).
He also made no attempt at any easy disguise in this way (like the amazon vest or OSHA vest criminals now often use). The get up did not look in any way shape or form official and was one of the amateurish weird things often pointed out (clumsy thick chemical gloves, cheapo mismatched holster, reflective stripe backpack) Just an alarming haphazard alarming look that does not match any official reason to ruse to be there., like he was cosplaying the Zodiac kiler or something.
Now what you suggest is often used by criminals whether a common porch pirate stealing a package or a hit-man masquerading as a LEO (think Minnesota political executions case where he dressed like a cop and flashed the light at the eye-level when they opened the door). It's very easy to do in both getting the gear and imitating behavior. I am surprised he didn't go cliche all black tactical ninja, or have a molle vest with a velcro patch on it (police/dea whatever) or just go the hazmat vest (removed so easily) and flashlight "M'am I here to check on a gas leak in the area". There seemed zero effort on both fronts here.