Both of those feel like possibilities, but probably not in any significant number. In absence of evidence to the contrary, I'd say it's reasonable to look at the results of a vote as evidence of how people actually feel.
Edit: Vote numbers seem consistent with other votes in Debian's history, so it does not appear that a large number of people elected not to vote.
It looks like it would need a General Resolution to allow secret voting for future General Resolutions.
They agreed on their voting system in advance exactly to handle cases where the vote might be contentious.
edit: I found those, so it's not that weird, but not very common: Init systems https://www.debian.org/vote/2019/vote_002 ; Delaying Lenny https://www.debian.org/vote/2008/vote_003 ; Change to membership procedures https://www.debian.org/vote/2008/vote_002
this may change in the future if enough people find that (optionally) private votes on resolutions are a good idea.
FWIW, some people didn’t want to vote because the results would be publicly with names.
So the result of a secret vote might have been different.