"Pilot shortage."
There was enough of a downward pressure on hiring minimums that would have likely resulted in near-historically short spans of time for a significant number of pilots going from a regional job to a major carrier had COVID or another 'black swan' event not occurred. We saw glimpses of this leading up to March 2020 / pre-COVID; everyone was hiring. All that momentum is now lost.
The industry will recover, but I'm afraid there may be more hurt along the way before things truly stabilize. Despite some touting record stock market highs and conflating it with an economic recovery, the stock market is not the economy. Business closures and jobless claims are still alarmingly high. Predicting the future is tough, but if I were to make an educated guess, we're not going to see the same time of boom in hiring we saw in 2016-2019 for "awhile" (5-10 years, maybe longer) and recovery will be fragmented depending on the health of various market segments.
The good news is that there will always be opportunity, however, it will be highly competitive; it's all about positioning one's self to capitalize on opportunities as they present themselves. Positioning = job credentials, networking, and timing. What's the statement about luck? “Luck is what happens when preparation meets opportunity" or something like that.