Can we delete the vacuumdb.sgml notes about which version each option was added in?

I was just looking at the vacuumdb docs and noticed that I had
neglected to follow the tradition of adding a note to mention which
version we added the new option in when I committed the
--buffer-usage-limit patch.

There are 3 notes there that read "This option is only available for
servers running PostgreSQL 9.6 and later.".  Since 9.6 is a few years
out of support, can we get rid of these 3?

Or better yet, can we just delete them all?  Is it really worth doing
this in case someone is using a new vacuumdb on an older server?

I just tried compiling the HTML with all the notes removed, I see from
looking at a print preview that it's now ~1 full A4 page shorter than
it was previously.  5 pages down to 4.

Does anyone think we should keep these?

David