I'm of the opinion that Telerik has the right to license their software as they see fit, including making it not available for packaging in Chocolatey, and legal precedent makes it much more dubious whether or not the existence of an accessible URL makes it legally OK for Chocolatey to package it than I think most people here are acknowledging.
That said, the commenter I replied to also called out Mozilla, and as far as I'm aware, the software of theirs that folks package is FOSS