IIRC, he always said that any OA model for ACM requires careful thinking about a sustainable business model.
In 2009 he argued [1]:
> "Indeed, the idea of unfettered access to scientific knowledge naturally resonates with many researchers, including me. So why doesn’t ACM become an open-access publisher? [...] ACM operates as a democratic association. If you believe that ACM should change its publishing business model, then you should lobby for this position.
[...]
The second issue is the business model of association publishing, for example, "reader pays" vs. "authors pays."
This is a legitimate topic of discussion, as long as we understand that it cannot be separated from the overall business model of the association. Just remember, "free" is not a sound business model."
In 2018 he wrote [2]:
> "If we are serious about open access, then we must discuss its underlying business model. Let’s get serious about open access!"
IIRC, he always said that any OA model for ACM requires careful thinking about a sustainable business model.
In 2009 he argued [1]:
> "Indeed, the idea of unfettered access to scientific knowledge naturally resonates with many researchers, including me. So why doesn’t ACM become an open-access publisher? [...] ACM operates as a democratic association. If you believe that ACM should change its publishing business model, then you should lobby for this position. [...] The second issue is the business model of association publishing, for example, "reader pays" vs. "authors pays." This is a legitimate topic of discussion, as long as we understand that it cannot be separated from the overall business model of the association. Just remember, "free" is not a sound business model."
In 2018 he wrote [2]:
> "If we are serious about open access, then we must discuss its underlying business model. Let’s get serious about open access!"
[1] https://cacm.acm.org/opinion/open-closed-or-clopen-access/
[2] https://cacm.acm.org/opinion/open-access-and-acm/