Sure, lots of people were not happy with Bush dragging the country into two wars, but most Republicans remained Republicans, and the angst (based on facts or otherwise) against Obama is what made the Tea Party Movement so big.
(Of course, there was the whole social media thing that became huge around the same time, but the design of social media doesn't favor one side over another...)
So the prediction sounds right? The Republicans have burnt the youth vote pretty badly and have never really recovered.
(See, e.g. https://www.pewresearch.org/politics/2025/06/26/voting-patte... and https://www.nbcnews.com/politics/2024-elections/exit-polls. Annoyingly, the polls don't cleanly break down into generations; Gen X would be the ~44-60 crowd for that election.)