It's correct, but perhaps incoherent. The idea is that the consumer of the document must use the default value for a server variable, unlike the default value of a parameter, for example.

the consumer of the document must use the default value

sure, the consumer must use it, as you say. but that's completely different than providing the value - that is not done by the consumer but by the document.

I think we're arguing semantics at that point though, and since you describe it as perhaps incoherent, maybe can agree that it should be changed? and if so, what would be a better wording?

Text will be reviewed to try and add some more clarity. @OAI/tsc doesn't feel the current PR accurately conveys the intent.

Suggest something like [edited]:
The default value to use for substitution, which SHALL be sent if an alternate value is not supplied. Note this behavior is different than the Schema Object's treatment of default values, because in those cases parameter values are optional.

We discussed the language proposed in my last comment on the TSC call today and had verbal approvals for the edited version above. @notEthan would you like to incorporate and re-submit?

@notEthan I went ahead and modified the PR with the proposed changes as we want to push out a new version. We can revisit it if still needed in 3.0.3.

thanks @webron, looks good to me