Dead end jobs with little to no benefits, no pensions, time off, low pay and few hours count as "employment".
Their parents and grandparents had pensions and could work at one employer for the entirety of their careers with growth opportunities, and could afford homes and healthcare while doing so.
Your hypothesis might be right, but I've provided data, and you're providing opinions. I'm fine with being wrong in my claim, but I didn't earn the downvote when no-one seems to have a clearer hypothesis with better evidence. First, show me that this shift is peculiar to 2008. And then show me that this is what teenagers are killing themselves over.
US GDP: https://fred.stlouisfed.org/series/GDP
US unemployment: https://www.bls.gov/charts/employment-situation/civilian-une...
S&P 500: https://www.macrotrends.net/2324/sp-500-historical-chart-dat...
US inflation rate: https://www.usinflationcalculator.com/inflation/current-infl...