I think Lewis' analysis was spot on.

He said that McLaren pushed way too hard too early on (didn't Piastri set like 5 fastest laps in the middle of the GP?).

When Bono was relaying lap time information of the cars ahead to him he thought "there's no way the McLaren's tyres will last, they've forced themselves into a 2 stop strategy", which did indeed turn out to be the case, and it opened the door to Ferrari doing the 1 stop.

They asked Piastri during the race about that, he replied that his front left was in a pretty bad shape. So I guess they concluded that they would lose more by staying.

IIRC in the post race interview he mentioned that he had bad graining on the front left wheel and they he didn’t think the tires would hold up. Both McClaren cars seemed to have more problems with that than the rest of the field

If he hadn't pitted but Lando did, highly likely Lando catches and overtakes him. Also, there is a good chance that Charles would have pitted a second time then overtook him as well. The tyre delta for both mclarens at the end to charles was huge, and the ferrari was kinder to its tyres than the mclaren.