> Telephony and mobile telephony operators have strong businesses to this day, despite being made interoperable by law.

True, but their business model also requires payment unlike all these "free" services.

Moreover, the interop requirements here seem to me to be more preventative of physical monopoly than anything else. Physical phone lines and wireless frequencies impose physical barriers to entry or are only usable without transmission interference. Without an interop protocol, it's clear the first mover would steal the entirety of the market.

Websites are not the same. They are an interface built upon an already interop'd internet, from tcp up to http. There are no barriers to entry apart from the barrier to physcially access the internet, which is already interop among providers.

> In my opinion, there is harm - creating unnecessary burden and confusion for everyone, especially non-tech-savvy people. It is tying people down to services via network effects, and then further harming them by exfiltrating their personal data and exposing them to advertising (either directly or indirectly, making the ads more potent thanks to aforementioned personal information).

I don't think inconvenience qualifies as legislation-requiring harm. Yes, it is a pain if your network doesn't centralize, but email is still completely interop and free (not your data) or low-cost if you set up a domain on your own or pay for private email.

Tools are generally adapted because they make life easier. It is super easy to snag a Gmail account and then use it to create a WhatsApp, or Telegram, etc. account and immediately start chatting with your friends via the app' identification of them due to your phone book. No argument there. But to say that because other companies have done it and attracted your other friends first, they must now be compelled to allow you to export the data elsewhere, or at least define their systems by some standard, makes no sense to me. We have standards already and there is no physical barrier to entry for competition. There is a reason new apps keep coming out, and the low barrier to entry is one of the main factors.

> But that's not true at all. People are coerced to use these services, and coerced to stay with them. That's the literal definition of network effect. I have to use WhatsApp/Facebook/whatever because my mom is there and doesn't want yet another chat app, and my local plumber only communicates through it. I have to stay, because neither my mom nor my plumber will move. The more people are trapped in the net, the stronger its hold. (...)

Email is an interop standard. You sign up for an email account knowing you can communicate to any other email account. When you sign up for FB, you know you can only talk to people on FB. The difference is by design.

Coercion by your network that is not inhibited by physical barriers to entry is a personal problem. Your mom only wants to use FB, fine. Just speak with her elsewise or explain to her why you won't use FB. This is a personal negotiation and is not of relevance to lawmakers. Similarly, if your plumber only communicates with potential clients over WhatsApp, find a different plumber if you don't want to use WhatsApp. It's really that simple. No other plumbers around? Great! You've identified a huge opportunity that you or anyone can fulfill.

> These platforms are as successful as they are exactly because your proposed solution is impossible to implement by most people. Again: network effect.

My proposed solution is not at all impossible to implement. Difficult? Yes, extremely, but let's not confuse impossibility with difficulty. It is possible, but you'll have to be willing to make sacrifices along the way. The golden light in this is that you currently have the opportunity to make a chat system that defines an interop standard. Build it and they will come.

Anecdotal: when I joined my current employer my manager requested that I download and install WhatsApp to be able to communicate with the continent-spanning team chat for production issues. I contested. WhatsApp was not an approved company platform, and I was unwilling to install it on my personal device. I would happily install it on a work provided device, but I would not carry the work device with it on 24/7 because I didn't want to leak telemetry, etc. data to FB. So I don't use it. The team does, but I don't. They reach me through work channels if necessary or directly by phone/text.