I’m a big fan of “let them live”. Killing the PCs is not the point of the game and where you can you should err on the side of not. But if a monster’s goal is to eat one of the PCs and it has the opportunity to do so, it will.And how would you square this with that's written on page 7 of the GM's Guide?Nope, if you're helpless, they just outright kill you if they choose to.
"As GM, you should basically never kill a defenseless player character."
I say this both as a GM and as a player who had their character swallowed whole a couple days ago.