Jesus no. FF sold higher than Carol and most of current Marvel. It had a huge dedicated following. Sales was never an issue but an excuse.
Seriously before Hickman we had Waid and Millar. Who were at the time HUGE draws. Marvel fags actually threatened a boycott if Waid was removed from the FF when Quesada attempted to get a new writer.
And before newfags claim Waid was never good please fuck off. Back then Waid was one of the big guns before Marvel and Alonso neutered the poor guy with Liberal politics.