If we were exactly as we are now, other than we were out of the EU, then we wouldn't be exactly as we are now. Europe would be a very different place if the UK had never joined the EU -- the EU would be quite different, for that matter. Different in what way will affect the answer. Not unreasonable to duck a question to which the answer depends on the exact, unknown, scenario.
In most scenarios I suspect I would have wanted to join. Although then again, that's assuming that I think in this hypothetical world the same way I do in the real world -- and heck, even that assumption is stretching it. I thought one of the criticisms of younger people was that they were only voting to stay in the EU because that was the world they knew. I dare say that *does* shape my views to an extent. But of course if we weren't in the EU then that wouldn't be the "only world I knew".