Portal64 required you to have access to one file from portal 1, portal_pak_000.vpk. It’s trivial to get that file. Either via google, or purchasing Portal, extracting the file, then getting a refund.
Revolution requires a continuously working copy of Portal 2.
It’s significantly easier for the general population to play Portal64 without giving money to Valve than Revolution.
Portal64 required you to have access to one file from portal 1, portal_pak_000.vpk. It’s trivial to get that file. Either via google, or purchasing Portal, extracting the file, then getting a refund.
Revolution requires a continuously working copy of Portal 2.
It’s significantly easier for the general population to play Portal64 without giving money to Valve than Revolution.