I think it's good to open the conversation. It seems like people are less rabid about it now so raising it isn't political suicide.
I don't know if a full rejoin now - 10 years after the vote and 6 after actually doing it - is the smart move. We left the EU far too lightly, due to temporary political circumstances that never created a robust consensus. But that doesn't mean we should rejoin just as lightly - we are where we are now, and even if it's painful it's important to learn from those mistakes. That might mean accepting a half-way house without full single market membership for a while.