Yes, although that's a MacOS restriction, and MST is already used in MacOS to carry multiple streams to a single high-resolution monitor. And as Asahi Linux keeps getting more usable, I hope it can be a viable alternative, so Apple's hardware can be used without MacOS's arbitrary restrictions.

But it worked if you installed Windows instead. So the hardware supports MST

The Intel hardware supported MST. It's unclear about their ARM hardware (and the suspicion is not supported from people who've looked into it).