Ultimately voting in was a non win situation. Had we done so, the EU would have been far been far more thick skinned to the British viewpoint because they would believe, probably incorrectly, that we would not endure another referendum. In turn Euro scepticism among the public, which had been on a steady upward trajectory before June 2016, would have accelerated and it is likely that the demand for another referendum would have become politically irresistible.
By voting out in 2016, I think that we have dramatically increased our negotiating power in any future rejoining agreement. I thought at the time that by voting out, the EU would make the concessions that they stupidly had not given David Cameron prior to the vote and we would have voted to leave on another plebiscite.
Under the inevitable landslide Labour election win later this year, I would think it is realistic that we will begin discussions to re enter the EU under much improved terms. By then it will be politically advantageous to back rejoining and we will go back in. I would suspect that Euro scepticism on the continent will mean that any future EU will be very different to the one we voted out of and the direction of travel for the institution will be more in keeping with the original trade aspirations of the Treaty of Rome.