I agree with this, but I think the trouble is...the where of it. To me, the obvious answer would be at the airport prior to boarding DME. BUT...what if people were exposed on the airplane, but still too early to test positive? Then, they will be exposing an entire bus full of people. Who would then be exposing an entire lobby full of people at a resort. And so on and so forth.
If airlines require tests before boarding, that would take away the need to do it at the DME counter. BUT, what if someone is exposed at their departing airport? And, the test was too early to catch it before they board the plane. Then, they have exposed those people on the plane....who could then expose other people on the plane, or the people in line at DME, or the people on the DME bus....or someone in the bathroom who would then go on to the DME counter. And so on and so forth.
Not only that, but even if they get on and off the plane scot free, between the gate and the DME counter, there are so many people and/or surfaces they could interact with. The escalator railing, elevator buttons, restroom surfaces, etc etc. And if you are exposed 5 minutes before you report to be tested, then it could be a few days into it, conceivably your whole vacation even, before you would even test positive.
So...ultimately, what's the point. Yes, you would likely catch a lot of people before they get on the DME buses, but if even 1 or 2 people are missed, or have a false negative...then the chain reaction from that could be hugely damaging.