People who have walked in sin and who speak harmful lies about them are taken back due to the whole TRUTH of spending all of eternity paying for their sin. And this goes for everyone as God made clear He will judge the living and the dead.
As for the gospel being preached to “those who are dead” Peter I feel; was speaking of those who has heard and accepted the “gospel of Christ” when they were still alive, but who died prior to his writing of this letter.
If this is the case as they were saved and martyred already, they were now alive in the Kingdom of Heaven! That’s how I take it to mean…
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