It's not "source available", that term already has a different meaning. The cathedral development model doesn't make the result any less open source or free software.
That’s why I said “effectively run as” rather than is. Cathedral does make contribution to software less open, that’s kind of its entire deal and what I’m talking about here. It doesn’t make it any less free, but then a good number of software companies sell access and closed versions of open source projects, so we continue to split hairs.