It’s Monaco. Hamilton drove as slow as he wanted everywhere except the straight and tunnel. Save all the ERS power for those 2 areas, and you would need a suicidal divebomb like Max did to make any pass remotely possible as long as you have a power advantage. Mercedes is way too powerful for the Honda to have a chance.
If it was a Ferrari behind him, I’ll bet he wouldn’t have been able to hold them back. His tires were toast, running 3-4 seconds slower than some of the cars behind in clear air and old tires. He was lucky that he kept his rears in good enough shape to actually power out before the straights. Only way he would have lost today is if the fronts failed completely.