> They are perfectly functionalFor the people building them, yes. For the people using them, they are basically a massive con. "We will help you communicate!" Yeah, because this will allow you to harvest my data and sell me more shit. "We have these great features!" Yeah, that other networks had 20 years ago and you killed to enable the beforementioned con and monopolistic practices.
> I've deleted my WhatsApp account 2 years ago and still communicate with anyone without issues.
Well, good for you. I have WA groups that provide information about my kids' whereabout, schoolbus info, all sorts. Can I leave them? Yeah, in the same way I could walk out of civilization to go live on Jakku.