There's definitely a reason why Verstappen's car is so fast here, but Hamilton's attempts to attack Sainz and Sainz's defensive moves are also part of why such a big gap opened up in such a short time.
But in these 5 laps, Hamilton tried several times and just couldn't find a solid chance to make a strong move on Sainz ahead of him.
Instead, their dogfight let Qin Miao fully recharge his ERS and close up to within about 0.6–0.8 seconds behind Hamilton.
If Hamilton hadn't constantly been able to catch Sainz's slipstream, Qin Miao would've taken him out long ago.
Unfortunately, Qin Miao got stuck in a DRS train again, and in this race his engine is already on the verge of needing a change, so its output just isn't as strong as Hamilton's power unit.
So before Hamilton made any unforced errors, Qin Miao couldn't find any really good opening to attack for the moment.
