All will cease at some point but we shouldn't wait too long just to be pragmatic judging success.

Yes. You don't have to continue to exist forever to be successful, to suggest otherwise would be to amongst other things suggest that no human ever succeeds.

Atom development didn't cease because it failed as a product. It ceased because the company building it was acquired by a company that had already built a (open source) clone to compete with it.

Atom is actually alive and well as a community project under the new name “Pulsar”.

https://pulsar-edit.dev/