I believe one of the selling points are the shared collections. So you have all the secrets and endpoints and whatever in collections that you share amongst a team. Now, noone has access to any of this and the hassle to set this up locally is way worse than you would think. Specially in large organisations.
So yeah, there are probably several companies looking for alternatives right now :)
What we really need is a community-driven alternative without lock-in.
Many other use cases are covered by great FOSS products, but somehow API clients are abused as a sync cash cow:
(minor correction, Obsidian broke the 3rd party sync, not insomnia)
Point still stands.
I agree it's an annoying problem, but it's hard to see a way around it. The developers was that they need some way to fund development. Sync tends to be the up sell target since it's more for power users willing to pay.
There are quite a few open source Insomnia and Postman clones. Since most of them operate on config and workspaces, I think syncthing is good enough for this use case at least.
So yeah, there are probably several companies looking for alternatives right now :)