I don't know how spoiler provider can expect people to understand whole picture when they themselves drop content in pieces.
First, we get short summary
Then full summary
Then panels and raw scans
And, at the end we get chapter.
Users who are reading short or full summary will base their opinion based on what they got because they haven't seen the whole chapter. Nothing is wrong with this because if they will simply wait for whole chapter then what's the point of having spoilers and spoiler discussion thread.
Whereas spoiler provider have seen whole chapter so they are on different footing than the users and thus either they should drop everything at the same time or shouldn't judge users who forms opinions on limited information