The majority of the pro-brexit voters main goal was to 'deport all them foreigners', which was impossible with freedom of movement. When brexit 'got done' and it turned out those brown people they saw at the doctor were actually third generation brits, but the nice white couple down the street were actually non-brits and were forced to leave, many changed their mind.

But the Tories and new-new labor won't even consider a re-vote. Heck, after 12 by-election losses, Tories won't even consider a general until statue forces them.