If a price of a ticket goes up 10/20/50 euros it's not gonna deter me a bit if I have to fly.

Most people fly because they have to, family gatherings, planned vacations, business trips.

The number of people genuinely deterred by a small amount in price is still going to be small.

Also, inflation adjusted, fuel isn't that expensive. 80/90$ a barrel are prices we've seen already decades ago.