Firstly, the business of air travel is going to change fundamentally.
Pre-pandemic, airlines and the industry was powered by business and first class travel. The pandemic has changed business travel. Zoom and WFH has shown that you can meet online and it can be as good as being there in person. Companies will scrutinise business travel - can a zoom or conference call achieve the same effect?
Business travel is going to be reduced, and with fewer business travellers, there will be fewer flights, and with fewer flights, there will be fewer seats in economy, to fill with leisure travellers.
Yes, there is pent-up demand for leisure travel, but this segment of the market is VERY PRICE SENSITIVE. Those low low airfares pre-pandemic, are not likely to endure. Sure, when planes fly again, airlines may offer promotional, cut-throat airfares. but it will not last.