Fonts aren't public goods. Same as computer programs aren't public goods either.

I studied graphic design and designed (by hand, and later "digitized" some using Fontmaker and Freehand) about a dozen of fonts.

So, about that "public goods" part... Are works of art a public good? I think, well... there isn't a very good definition of what constitutes public good. Usually, this is used in the context of economics, describing a good or a service managed by the government and provided to most of the population governed by the said government.

Some works of art do provide a service, in a way (well, entertainment is a kind of service, right?) and some are sponsored and otherwise managed by the government. Not every work of art earns the same attitude. The governments are very selective about what works of art they put on display in museums that are free for the general public to attend. Museums are public good though, right?

So, back to the fonts. The ones I developed, well... they are barely more than just an art academy student projects. I showed them to couple of my friends and my dad... and that was it. I doubt the government of whatever country I end up in will want to invest much efforts into preserving those. However... the teacher of my teacher (when it comes to fonts), Bazhanov created this font: https://meganorm.ru/Index/42/42375.htm . The "ГОСТ" in that document means that this font received a government-managed identification number. The font is still in use today, and the government released the IP of that font to the general public to use. I don't know if the government has any kind of a digital storage for the modern fonts and how would they be admitted there, but, back in the days when the linked font was accepted into publishing industry, the original films with the letter outlines were placed in an archive managed by the state's standards committee (that's what "ГОСТ" stands for).

Bottom line: it's complicated, and fonts aren't automatically public goods, but some of them are promoted into being public goods, based on many criteria, so, it's not easy to tell which are public goods and which aren't.

The historical record is a public good.

The historical record isn't saved as Adobe Illustrator and InDesign files.

Final products are saved in things like PDF's which continue to work just fine.

At some point, does not the software itself become part of the historical record? Otherwise we wouldn't care about things like the Internet Archive hosting its DOS emulator.

Not with that attitude