Echoing the comments there... this seems like a colossally dumb move on their part. Is there any way this doesn't just end with a hard fork and some new player taking over where Arduino left off?

The other option is that Arduino simply fades away. Their hardware doesn't have anything to offer that you can't get on aliexpress or spin yourself for a tenth the cost.

The framework is the only arguably valuable thing they offer, but even that's not enough to prop a business up on.

Most likely everything will continue exactly as-is: Arduino hardware will become increasingly dated and undesirable, and open source Arduino-compatible libraries will continue flourishing until nobody remembers that Arduino was a hardware platform before it was software framework.

I think we've long since passed the point where Wiring will ever go away, but I doubt we'll still be calling it Arduino for too much longer. Arduino is probably dead, and espressif is moving in.