NOBODY knows for sure what happens at any company for any significant length of time. Retirements at least give insight into how many have to be hired in order to just not shrink.
History shows though that if sheitz hits the fan some airlines will shrink.

Best time to buy Amazon stock was in 1997 as well. I remember people pouring $1000's into it in 99-00 and the company was losing millions quarterly. Turns out A $10K investment at it's IPO was worth over $16M two years ago (its 25th anniversary). That same investment is now worth over $24M just two years later.

As the Egyptian's used to say, "hindsight is 20/20"