Bull Shit! Biden is safe as long as the Democrat hierarchy want him to be safe. They will replace him when they want to replace him.
They believe he's safe because they believe, as of now, that 2024 will be a slam-dunk repeat of 2020.
They also know they can't replace him because Kamala is the next in line and she polls even worse than Biden does. Denying her the top spot will lead to an ugly, expensive primary battle.
No, they'll keep Biden and if the nightmare of 2016 starts creeping back into their consciousness, they'll work towards other methods, primarily ballot denial in key swing states.
And if Trump wins a write-in campaign, there will be endless recounts. If this fails, they'll work on faithless electors.
No matter what, they will play every card they have before Trump is allowed back into the White House.