As usually, I blame FIA for inconsistency in applying rules. Since Hamilton and Raikkonen Spa “incident”, it was deemed that you can not overtake car that you let through immediately, or in a place that will give you advantage. (I don’t know what is the exact wording of the rule, tried to find it and failed).
Sometime this rule is applied, and sometime not, and that is on FIA. It is difficult to put into words what would be the place where you should let another car overtake, but I thing that it could be something like time constraint.
If the longest straight full speed is something like 10 seconds (Baku around 2 km), rule should be: Don’t pass car that you let through in another 10 seconds. That would cover even the longest straight in the calendar and would work for any race.