Where do people get this notion that every system has to work with their competitors’ system? Genuinely curious. Why would I spend resources making sure to accommodate connection to something that competes?
1) It used to work that way. You didn't even have to put in special effort. It takes more effort to do what these companies do today to ensure nobody can interface with their service.
2) Apparently we need regulation to make companies do it today, and that will force these companies to allow interoperability.
This is what the internet used to be like. Nowadays, something like this would be unthinkable. But you could use Pidgin to connect to Facebook Messenger, AIM, ICQ and MSN. No, you couldn't necessarily use your AIM account to talk to somebody on FB, but that was only because the companies making these services didn't implement this. The fact is, it could've been done if they wanted. The technology was there, the environment was there, the open standard that almost everybody was using was there.
Now you have Discord, Facebook, etc. banning third party clients and enforcing a walled garden when they don't have to. It's a conscious choice they're making.
I'm not sure why you're defending the current state of things. It's worse now.
Because one day We The People will pass Apple Laws which levy a 100% final point of sale sales tax on products (containing at least one universal machine) and services which reduce owner sovereignty.
If a product could conceivably do X and steps were taken in R&D to keep it from doing X (not that it wasn't implemented, but was specifically designed to prevent owners from doing X even though otherwise it could if steps weren't taken), or if the product maker does not publish protocols, formats, standards, etc, or designs those with the intent to thwart interoperability; or if the owner is prevented from changing programming code on a universal machine regardless of the product's function (phone, PC, microwave, washer, blood sugar monitor, automobile) with well-known interface hardware and communication protocols; or anything else in this spirit I have missed, will be in violation of Apple Laws and must have a 100% final point of sale sales tax levied so that philosophically highly anti-Stallman products can't compete easily against near-Stallman compliant products.
Closed source proprietary software and hardware are huge national security problems. Even if USGOV can sign an NDA to inspect source code and chip design, it's still a national security issue that you and I can't. It is a national security issue when decade-old idiot-TVs and idiot-cameras long out of software updates pwn computers and/or get turned into remote surveillance devices for digital voyeurs paying top dollar to collect private feeds into peoples' lives (don't ask).
