Maybe I got you wrong, but:

Today, if the package has enough votes it only gets unlocked for the promotion to extras. The maintainer has to manually promote it, to get the package to extras. So if the packages was able to get through the voting, the maintainer still has the choice.

Actually, by browsing through extras-testing, I saw a package which had many comments like "the maintainer should promote it to extras" and had not yet done so... but I forgot which app it was - so I can't give an example .

And btw. I also don't know when a package gets unlocked ^^... the package I have in extras came there with only 3 votes... now I have 4 (actually 5, but one from myself ) and the quarantine period is over and I still can't promote it. So I guess the "promotion unlock" is also a manual process.

As you see even maintainers don't know the process (maybe I'm a bad one ).