Where do you think those streams for the app. originate? From "Police Scanners" owned by scanner hobbyists, who provide the streams for Boadcasify to which most of those apps. connect. Also remember the Terms of Service for those streams exclude any tactical and other similar type channels from being streamed. Thinking that a police scanner app. is all you need is laughable.
My point being people were asking if the gunman/perp of this incident had a "police scanner" in the hotel suite with him at the time this incident took place and so far we don't have a yes or no on that aspect of the situation.
For the record: I don't own a physical scanner anymore, I haven't for some time - I did own a Pro-668 for a week or two earlier this year when I was still living in Las Vegas - and I use an RTL-based USB stick aka "a cheap USB TV tuner" to monitor such comms. I could easily set up a stream in 5 minutes of my current living area (but there already is one, so that's not really useful I suppose) and I don't need a physical scanner to do it.
As for the exclusion of tactical and similar type channels, all THOSE specific channels in Las Vegas for LVMPD ARE already encrypted and these comms during this event, because of things going so haywire so fast with all the events happening all over the place in that area on LV Blvd, were not being broadcast over those encrypted comms for obvious reasons (interagency comms, support, etc).
I can absolutely assure you that during all of this investigation that's now going on there is also a major review happening of the radio comms during the incident start to finish and they will ultimately make some drastic changes for the future which could lead to encrypting even more content.
This was a terrible tragedy but there simply wasn't going to be any way to prevent it and in the future there still isn't going to be any way to prevent it from happening when someone puts themselves on a course of action like what happened.
There's no fix for Humanity, never will be.