That is _one_ definition and comes from an organization with an interest in loading the term.
The OSI surely has some say in what they meant when they created the term "open source". The term didn't exist before 1998 when the people involved† with the organization you're referring to coined it. Anything else is just perverting a well-defined term.
I'm not a huge OSI fan, so when I say this, it's not coming from a place of ideology. It's just historical fact.
† The organization didn't exist yet, but it was founded later that month.