1. The only way for businesses to release their core products under OSI-approved licenses is through a time delay such as the BSL.
2. It's good for businesses to release their core products under OSI-approved licenses.
3. Therefore, some concept of time-delayed release must be included in the definition of open source.
I'll concede that this is an evolution or refinement of the definition of open source, but not a change to the essence.
[disclosure: I'm Head of Open Source at Sentry, which owns Codecov.]