They did good work in absence of anyone maintaining the product, but they're running software on a product they literally did nothing to build.
Core could easily say "actually we won't support Rebble at all it's too complicated to maintain this relationship"... and Rebble would then only exist as long as people are willing to maintain the now decade-old original watches... which is a difficult task given the availability of superior hardware from the original manufacturer.
With the Core deal they could actually grow and they get a significantly longer lease on life even if the hardware company fails again.
This seems a little silly, no? rent seeking behavior for maintaining code they didn't write to begin with?
They're entitled to it just because in some sense Core is a successor to Pebble? No, not really.
No one's actually entitled to anything here on either end (legally), I see 0 work being done to actually contact the original authors to seek permission or licensing details.
AFAIK, there wasn't a blanket license that covered all apps in the ecosystem... so each app would vary. In the absence of a license all rights are held by the original developers.
Again, if that's all it were, Core could and should just take that old Pebble dump and use that. Why bother Rebble if they haven't done anything as you imply.
If Core were to do the same thing here, it's not the same, because Rebble is still active. You can't kill what's already dead (Pebble), but Rebble is very much still alive.
And how would this prevent Rebble from continuing to operate in the event that Pebble failed again?
Open sourcing the OS makes continuity in the event of a failure much easier for Rebble right?
They embraced the the pebble community with a copy of the App Store, extended it with their own weather apis and the like, and then now are trying to extinguish any ability for Core to implement their own solution without paying them more.