It wasn't unilateral (assuming a definition of
"unilateral" similar to
the English-language one). I can personally assure you that there were
others working with me.
There was plenty of support for removing them, so it was far from
unilateral. Whether or not there was a consensus is questionable, but
there was certainly a large amount of support.
The matter wasn't helped by people not reading the articles carefully
before removing tags, though - for example, I had to replace a spoiler
tag *twice* in a particular article that was in the Cast section just
before it was mentioned that a member of the cast had left following
the death of their character. A Cast section is most certainly not a
plot summary or anything similar - if it is ever right to use spoiler
tags (and there most certainly is *not* consensus to remove all tags),
then there should be one there.