> perhaps made possible by restricting distribution of software in the first place to get a leg up
This is incorrect, you can download the full ISOs for SLE from the SUSE website, with 30 days worth of updates. The source code (and the system required to build it) is all publicly available on https://buid.opensuse.org/. I beleive RedHat have something similar.
I'm also not sure that an interview from 1994 with the creator of Slackware is a good indicator of the current state of distribution business models. Though even in 1994, both RedHat and SUSE were selling enterprise distributions.
Since the past determines the future, the relevant part of the 1994 interview is "... Instead, he claimed distribution rights on the Slackware install scripts since they were derived from ones included in SLS...", which as I understand it, is the restriction of distribution I was referring to (perhaps redistribution is more accurate).
This suggests that the business model benefited from restricting redistribution and modification of the source code, so breaks the assumptions that the business model was purely based on making money from open source, and so doesn't fully support the idea that proprietary software is unnecessary, in the case where we take SUSE as an example of saying it is "already solved".
This is incorrect, you can download the full ISOs for SLE from the SUSE website, with 30 days worth of updates. The source code (and the system required to build it) is all publicly available on https://buid.opensuse.org/. I beleive RedHat have something similar.
I'm also not sure that an interview from 1994 with the creator of Slackware is a good indicator of the current state of distribution business models. Though even in 1994, both RedHat and SUSE were selling enterprise distributions.