I don't think the real focus is on the tags, but on the delay here via a form as well as human interaction.

Worded differently, the simplest way to provide the source code is IMO via a URL that you can just wget. At the least this is done by so many projects out there. Google refusing to do so means Google wants to violate the GPLv2, since their alternatives are inferior.

https://distrowatch.com/ has many convenient links to URLs on the left side; I often use that to download the latest and greatest and compile it away, e. g. https://ftp.isc.org/isc/bind9/9.20.27/bind-9.20.27.tar.xz as a current example, taken from the left panel.