That has turned out not to have been the case.
Just how old is anyone who is motivated by "Imperial nostalgia"? Far older than Vince Cable, for a start.
But in my experience, Brexiteers range from youngish to very young indeed: Andrew Fisher, Alex Nunns, Liam Young, Matt Turner, Max Shanly, George Aylett.
But then, those are all on the Left, and closely associated with Jeremy Corbyn.
You know, the Leader of the party that won the seats that had swung the referendum for Leave, across Wales and the North of England.
Had the last Parliament run its course, then the Remain heartlands of the South would instead have swung to the party that Cable now leads.
If this Parliament runs its course, then they will.
Meanwhile, the Remain heartlands of Scotland have largely swung to the party that has so far retained the ones in the South.