I said first entry into 121.
My entry was Oct 2007 at my regional. 2 months later, Age 67 went into effect. Less than 12 mos later, the GFC which was 2008-2010ish. 2008, 2009, 2010, 2011, and even 2012. Solid years of virtually no hiring at the big boys. AA, no hiring. UA, furloughs. Delta hired about 300 (?) in 2010 and that was it. Now granted, it was hard to define the big boys because they were merging at this time. 2008 Delta/NWA. 2010(ish) Continental/United. Airtran/Southwest too. And then US Airways/American. I still remember AA opened their window late 2013, I believe November. I know because I applied that very first night and the whole system crashed. Yes, crashed. There was just that much interest in AA. Or anyone big for that matter. YEARS of no hiring at those airlines left many pilots on the sidelines just waiting.
In 2008-2012, the game in town (and hardly a game, still more like slim pickings) were jetBlue, Spirit, and Virgin America. Can't comment on Frontier or Allegiant back in those years, but I imagine they were about the same.
The "real" big boy hiring didn't start until 2014. So my point was anyone who entered into 121 flying at 2014 or later, has seen only the good times. Covid was a mere blip that didn't even in result in anything solidly bad (barring a few regional carriers). If anything, we let tons of seniors retire early and created a huge lack of pilots which led to MASSIVE hiring.
If you *entered* a 121 in 2014 or later, you haven't seen the true hard times. Just sayin'