In the long term (20 years) people will still be arguing over whether Brexit made any difference.
I'd like to think that the legacy of Brexit is that the govt & parliament, having been given a bloody nose by the backlash of the long ignored & wilfully forgotten working classes, use the opportunity to improve the lot of those outwith London.
Not by repeating the Labour finesse of the 90s & 00s where they just invented public sector jobs and propped up low wages, but by meaningful plans, investment and redistribution of power & private sector work.
We may still be subject to free movement to an extent in the future, but the impact would not be as disproportionate & devastating as it has been up until now.
Thus, even if immigration is broadly similar in levels, it won't feel as catastrophic as it does to many now.
The legacy of Brexit, even if still 'signed up' to many EU rules, would be that we are no longer locked in - we could presumably leave a mutual agreement with less fuss at any time.
Also, even if we still pay 'membership fees', then that will be a fraction of what we are paying now.
I don't mean the headline figures 'This Is What We Pay!', I mean the hidden costs - the travel cost, subsistence, expenses, food, accommodation, accompanying entourage etc.
Britain will be far better off out of the EU.