New travel measure doesn’t make sense

UP until last week, travel into and within Papua New Guinea wasn’t restricted, but National Pandemic Response Controller David Manning has changed that.
He said those travelling to PNG should be in quarantine for 21 days and be tested, at their own expenses, three times.
Why has nobody questioned Manning about the logic of this decision?
Where is he getting this advice from?
Our tourism industry is on its knees and in dire need of resuscitation.
Allowing fully-vaccinated people to travel to PNG and be in quarantine for seven days would be reasonable and would be considered an option for tourists, but why 21 days?
This measure does not offer any incentive to get people vaccination as there is no reward, only disadvantages.
What about the rules for travelling within PNG?
Given the low number of vaccines administered, how does the controller expect any airline to schedule flights to cater to a total pool of potential customers across the entire country of only 18,000?
Prime Minister James Marape was quoted in The National encouraging trade between PNG and its Pacific neighbours.
It is pretty hard to see that happening while trade envoys who are fully vaccinated are expected to quarantine for 21 days if they need to travel to PNG.

Stephen Lane