BeOS?

"Android's binder [...] first shown up as part of the BeOS system"

I can't find any evidence that this is true in a meaningful sense. It's correct that people behind Binder (and thus OpenBinder) worked at Be Inc. but if Binder was part of that work it seems to have never shipped to end users.

It is of course hard to prove a negative. Little pieces of binder might be present, undocumented and largely unused, in BeOS R5 without anybody knowing. But certainly if it's there its presence was so unfelt that BeOS clone project Haiku (once OpenBeOS) has nothing resembling binder nor any indication that it thinks such a thing is needed or desired.

Some documents assert that Binder was the IPC mechanism in BeOS. In fact BeOS IPC is an asynchronous message passing system built around the BMessage type-length-value flattened data structure - it has little surface resemblance to Binder's synchronous local procedure calls.

The next item in Binder's history is PalmOS. That's huge, a well-loved product on handheld devices. Except, it's referring to PalmOS Cobalt (6.0). That's the version developed by Palm spin-out Palm Source, and not only was it not successful as an independent venture - Cobalt was never even used on Palm's own hardware, maybe Binder made it awesome, maybe it was a disaster, end users will never be able to try it for themselves.

It seems to me as though somebody successfully painted Binder as a project with a real world pedigree when in fact, for all the enthusiasm of its developers, Android was actually the first time it was used in anger in a consumer product. That certainly makes it easier to understand how it shipped while still "horrible" and "broken by design".