[SECProto]

> Porter Airlines appears to have started in an entirely unique regulatory regime, actually

I did a quick skim of that wiki article (skimmed a couple sections, ctrl+f'd for "regulat" and "monopoly"), but couldn't find anything about a unique regulatory regime. There has been regulatory issues with the Toronto Island Airport (where porter wants to extend the runway to allow jets to land, but no one* else wants this), but I don't see where they required a unique regulatory regime?

[closeparen]

No one wanted it because it would have meant more flights. That's precisely my point. There is no such thing as new traffic capacity anymore. You can only take it from someone else.

[SECProto]

> There is no such thing as new traffic capacity anymore. You can only take it from someone else.

JetBlue started in the late 90s, and according to the wiki [0], "was awarded 75 takeoff/landing slots".

Sunwing Airlines [1] started about 15 years ago, with departures from Toronto Pearson. They targeted the southern vacation niche. I don't know the details of the traffic capacity at Pearson, but they didn't get their landing slots by buying some other airline.

I'm not disagreeing with your comment about the limitations of dividing up a limited resource - many airports in North America are at capacity, and there's no room there for new competition to start up. But you followed it up with an absolute "You literally can't start an airline from scratch", which I took issue with because there are several examples that disprove it.

[0] https://en.wikipedia.org/wiki/JetBlue

[1] https://en.wikipedia.org/wiki/Sunwing_Airlines