You're missing the point, Burney. Many Remain people voted Labour because they didn't want a hard Brexit and the Tories having a strong majority seemed the most likely way for that to happen.
It wasn't about the Labour manifesto, it was about weakening the Tories so that they had to compromise.
BTW, I don't think anyone committed to a hard or soft or full Brexit. I don't think anyone ever has because no one has ever really attempted to define what it meant. Which is one of the reasons I didn't vote Leave.