Hiring is cyclical in aviation. The industry is a leading edge indicator of economic prosperity and decline, though faster to decline than recover, and there's a high probability that in your career you'll find yourself losing a job with short notice (furloughs, bankruptcies, mergers, downturns, etc), and that hiring will become scarce for periods of one to several years.
Discounting unpredictable intrusions such as the pandemic, aviation has typically rolled on a ten year cycle with highs and lows, but this is imprecise and unpredictable.
Bear in mind that there is far more to do in aviation than fly for the airlines. The path is not as narrow as some may think.