@snood,
Bolton isn't a lefty (boy I'll say) so attacks on his credibility have to take the form of "deep state" or "disgruntled former employee" or "books sales".
But it is an interesting move for Bolton to write this book as he's written it and with the charges he makes. If the release of this information results in Bolton testifying or in an extended court case to prevent him from testifying, much of the Republican world is going to do what they can to hurt and cripple him. Just imagine what Trump - Vengeance is Us - will do.
So, it's puzzling. As one writer pointed out, Bolton was tutored by Dick Cheney in the covert murder of opponents. Is it possible that some want to get Trump out of the way in order to do a conservative re-set or rebranding? Is Liz Cheney really, really hungry for power? Much of this stuff is out of sight, of course, so god knows.