I think you're tripping yourself over with "public." The implication (at least that many hear) behind "public" is "state-managed." For the most part, I don't think many people want that. What you're really looking for is "commons." It's technical but IMHO worth introducing.
Thread · 3 tweets · 26 Jan 2022
You might be able to piggyback off the vague understanding that coding folks have of the creative commons and keep them there long enough to get your point across before someone says "but crumbling bridges!!!"
• Source Code Commons — It Takes A Village Not To Poison the Well
• Security In Numbers — Open Source is Infrastructure, Commons Keeps it Safe
• I Hate Maintaining Infrastructure — With Open Source We Can Hate Maintaining Infrastructure, But Together