Wondering why we're not hearing this on mass media, regardless.
This always seems like such a disingenuous and loaded thing to say, as if the evil big media is deliberately ignoring news when it doesn't coincide with its hivemind agenda.
One, the ultimate impact of this is low. Same reason why one person dying in a car accident doesn't make national news while a bridge collapsing and killing 6 does, or why a small company getting hacked doesn't get picked up while one leaking the personal data of 50 million people does. In the end, one person was killed. That's cold to say but ultimately not that big of a story.
Two, it's looking like the shooting was targeted after a breakup
and, according to the police, "not a random act of violence". It's very questionable that the shooter was planning a massacre and pretty unlikely that another major mass shooting was stopped. The media attention would probably have been greater had the officer stopped someone going on a rampage in an attempt to kill as many as possible, not a kid who couldn't deal with a breakup and was out for revenge.
And three, literally every single mainstream media outlet has reported on this and usually several times too. The OP directly links to CNN but a quick google search will show you that ABC, NBC, CBS, Fox, Washington Post, NY Times, NY Post, Reuters, AP, NPR, Vox, Al Jazeera, PBS, CBC, The Hill and many, many others covered it. It even made it overseas where the BBC, Guardian and Telegraph all ran pieces on it. It was on the Reddit front page and even found its way to my Facebook the day it happened. It definitely gathered quite a bit of media attention.