The landscape has shifted dramatically since the referendum. Don't believe anyone on either side that says it was clear what the choices were. That future doesn't exist anymore.
Given that... The UK should reassess its relationship with the US who have proven to be as bad if not worse than Russia for our interests. That only leaves a handful of options. Join back to the EU fully, join the EEA + bespoke (probably best given the fractured nature of politics in the UK), go it alone. Going alone has not proved as beneficial given the US has basically shat itself politically.
This is much more about simple (😂) trade and GDP. It's about security issues, political alignment on issues such as Ukraine Greenland Canada Falklands, threats to democracy from Russia Israel.
The tone is welcomed from more and more senior figures in the EU. But the UK needs to be vocal about the harsh reality it faces trying to chase the US's tail.