What is the best practice for a quarto revealjs document to also offer it as a PDF? Can I configure the metadata in a way that there would be a proper quarto command for creating the PDF out of the revealjs presentation that i could then link on a talk page next to the revealjs link?
Revealjs offer a view dedicated to correct printed output.
However, there is currently no way to print to PDF from Quarto CLI directly. You need to do it manually using this link to print on Chrome for example, or programmatically using R to serve the presentation and print with chrome.
We'll be added the print feature in a future version probably