If it's harder to find a job in the next five years as a senior engineer, it will likely be because the economy is in a recession or because of simple reversion to the mean, not because of too many entry-level engineers entering the workforce. If there was any time when entry-level engineers were flooding the market, it was during, like, 2013, when Google and Facebook were hiring like crazy.

The unemployment statistics don't match what you're saying here, at all.