If Beeper Cloud uses a Mac in the middle then I would have assumed that is actually permitted, as its presumably a legitimate iMessage client and some software to forward your messages after that.
It seems similar to the parallel of iOS builds where its been possible to do so with virtualized MacOS on non-Mac hardware for a long time but its a violation of the TOS of MacOS to do so. Apple does spend effort ensuring that companies running cloud builds do so on Mac hardware; they don't care that the true end user is running Windows and achieving an iOS build as long as there was Mac hardware doing the actual building.
So this reply is along the lines of "we did something for 3 years that allow and they never stopped us" which isn't very strong evidence they won't stop you now that you're doing something they don't allow.
They may not do anything here thanks to the current EU climate though, I only mean that the fact they did nothing about Beeper Cloud is not evidence one way or the other.
The game being played here is poker. If they call beeper's bluff then they risk setting a whole industry wide precedent that interop supercedes ToS (that's the only angle).
As it stands, ToS based C&D for interop is untested afaik.
We as a community need to discuss ToS-trolling and fight against it.
unless the EU rushes out their legislation that interop is not grounds for terminating someone's account, I'm sorry, but they can do whatever they want to with their app.
Would you feel happy if someone used your home network to seed torrents? Using your bandwidth to seed them?
That's the only reason I'm not confident that Apple will kill this. They wouldn't want the regulatory attention and (at least for now) this is a niche area that few people know about.
Except that Matrix never profited from it. Beeper is the first company to provide a paid service for it and had their own servers. But now they are providing a paid (with a free tier) service that runs on Apple/Meta/Signal infrastructure.
This is asking to draw unwanted attention towards yourself.
Do you remember back when Pidgin, Trillian, and others created clients that worked across AOL, MSN, and other messengers. They worked for a while, they'd stop working, they'd update and start working, and that went over and over again. I'm not really looking forward to having that experience again.
We haven't had a single problem like the one you're describing. Not to say it will never happen.