How often have we seen Max yield a potential fastest lap when he has the car/tires for it? I'd like to think Lando taking the fastest lap was a sign they had more left in the tires, admittedly with more management, than the lead Red Bull.
Max even mentioned in the post race interview that it was really the middle stint that gave him the gap. After that the pace was similar, so I think if McLaren can get their high fuel running deg under control they'll be competitive.