You are absolutely not spot on.
In summary
There were many reasons for Brexit, and most are still there there. For me UK sovereignty was and is one of the main reasons. And the fact that the EU seem to perceive we are still a member and want to punish us for being naughty should come as no surprise, it doesn't to me, I always thought it was going to happen.
The EU core principle may well be a level playing field, but sadly that doesn't work given the diverse political, cultural and economic differences of each of the member states. Plus the major players, France and Germany, seem to wag the dog to their advantage. Strasbourg to satisfy the French anyone?
And we have tried to fit in in the last 20 years and it didn't seem to work. We always seemed to be the odd one out. We tried to negotiate our situation following the Referendum and they basically told us to stuff it.
Many on this forum won't remember the Common Market which was a trade organisation and a predecessor to the EU. De Gaulle kept us out of that, bringing new significance to 'Non!'. So much for European friendliness and cooperation given what had happened a few years earlier. But things changed a generation later and we enthusiastically voted to join the EEC, another trade organisation, and I voted in. But since then the EEC trade organisation has morphed into the United States of Europe with significant and increasing pressure to conform to its rules, laws and regulations, sometimes against the national interest. So I would still vote leave. But if it had still been a trade organisation, we wouldn't be in this situation, but it isn't, so we are.
But at the end of the day, we have left the EU, trade agreement or not, and we are going to find the world is different for other reasons too which have affected the rest of the globe this year, and we will just have to get on with it as we have done before, rather than carping on about the what would have been.