The "rules" you cite are to "protect the president from being manipulated" are not working. Those rules never envisioned a president like Trump for whom no guardrails or ethics lines are a hard stop.
Biden didn't "fuck up" when he first asserted he would not pardon Hunter. I don't think Biden lied. He made this comment early in the investigation.
Changing one's mind because circumstances changed does not make it a lie.
First, Hunter had a plea bargain for two crimes (lying on the gun form and not paying taxes on time) for which almost NOBODY ever gets charged with. But the MAGA cult wanted to exact pounds of flesh from Biden and his son undermined the plea bargain. Hunter would NEVER have had to go to trial at all on this had his last name not been Biden and his father not been president. For all their talk of weaponized justice system, this is exactly what it looks like.
The second thing that changed was Trump's pick as head of FBI- Kash Patel- who has openly vowed to go after journalists, networks, any of Trump's opponents as well as Hunter- again.
Does anyone really think Hunter, if sentenced to prison or jail, would actually be safe? I don't.