> You can VACUUM INTO, but standard vacuum won’t rewrite the whole db.
This is not true. From the link you posted:
> The VACUUM command works by copying the contents of the database into a temporary database file and then overwriting the original with the contents of the temporary file.
I am not sure if you're supporting, or opposing what Moolenaar does here. But a large difference is, that, although i am not sure if there's any sort of transparent reports available on the project, they don't ask "donate so I can keep working on vim", they specify "Donate to help poor Ugandan children"
I think this explains the lack of viewers; they are simply not needed.