The Bright Data “free” VPN they’re talking about requires the user to go through steps to enable it.
These aren’t as simple as downloading a free game and then the phone is compromised as long as it’s installed.
The users who install these things don’t care about permissions prompts. They’ll follow instructions to tap any prompt the instructions ask. They want the free thing and don’t care what they have to do to get it.
The article also talks about NetNut, which was embed in many apps released into the app stores.