can Perez fight for the title against Max until the end of the season?
I don't think the other team can gain 1 second per lap in races to compete with them.
The gap is only six points for now and it is normal to think about this as a result. However I'm not sure whether Perez can be that much consistent throughout the season. Because he tends to make more mistakes than Verstappen normally. If he doesn't work hard regularly for keeping this level then I think Verstappen will pull away from him at some point this season.
Perez seemed pretty decisive about competing hard against Verstappen in this season according to his statement before the season started. Because you know there was some problem between these drivers last season. Perez couldn't see the same help he does for Verstappen. Instead Verstappen even managed to make him annoyed by making an interesting statement after that. Maybe this ambition can help Perez stay in the title fight for a longer time.