Newt wasn’t slammed for making money from books. He was slammed for using a presidential campaign as a thinly veiled book promotion tour. Your book is supposed to promote your campaign, not the other way around.
He was also slammed for accepting a $4M advance on a book he penned in the aftermath of the 1994 election...he cashed in as the incoming Speaker.
Rush spent weeks defending Newt. It was legal, but I thought it was Washington business as usual, i.e. scummy. Newt finally caved, returned the advance and was compensated for royalties.
If Newt was so convinced he was right in the first place, he should have told everybody to FO.