

600k people being jailed? Very unlikely, the UK doesn’t even have 200k serving police officers in total and prisoners have been released early because there’s simply no space left for them. I’d be surprised if even 1% were arrested. The UK brought in some super draconian protest laws recently though, so no doubt there will be some, especially given what the protest is for.
I’m guessing you’re in the US. In many parts of the world including where I live, it’s the messenger app. If you don’t have WhatsApp you’re pretty much not communicating with most people.