As a Brit living abroad in the EU, I strongly opposed Brexit. Turkeys don't vote for Christmas. All EU citizens in the UK and Brits in the EU had to be transferred (often by application) to a new residence status. This process was leaky and many people lost residence.
A few years later, the dust has settled.
While I was a strong Remainer, I'm not sure I'm a Rejoiner, not only for the obvious reason of the UK not being likely to regain its privileged deals should it rejoin.
The macro-economic damage from Brexit is far less than I feared. One has to play games with statistics and employ assumption-heavy counterfactual models to see big effects. Countries adapt to new realities.
The EU is in an economic and social mess (much like the UK). Its energy policy predictably imploded and the engine of European economic growth (Germany) is in a worse state than I've ever seen. I lived in Germany during the 1990's, speak (my own version of) German. I love the country and the people. It gives me no schadenfreude to point out its present weakness. When it comes to immigration/social policies, the EU electorates are choosing leaders who would make Farage blush. The EU is not in a good place right now.
As an economic bloc, the EU has shrunk relative to the rest of the world. One can always play games with stats to try and show that all is still ok but this is tiresome. The Commission accepts that the situation is dire, as confirmed by Draghi report.
The only conceivable large-scale practical benefit of Brexit is the ability to make better regulation (regulation is the main work of the EU), especially as we're likely entering something approaching a new AI-driven industral revolution. The old saying that "the US innovates, China replicates and the EU regulates" is a little unkind but there is some truth in it. The EU is not producing Amazons or Googles. This is a (big) problem.
Regulation was the main cause of the wrangling between the UK and the EU when they negotiated the trade deal that followed the Withdrawal Agreement. The EU wanted the UK to follow its regulations/law and court judgements on a massive scale. This was a very unusual demand for a trade agreement. The EU was well aware that regulation is a potential Brexit win. The UK resisted and got a bog standard free trade agreement, which is it all it wanted in the first place. This is probably wise.
The only thing I much cared about when it came to the EU was Free Movement. It's unfortunate that Free Movement was a driver for the Brexit vote. However, you don't need a political union to have the freedom to move between states. We have free movement with Ireland. The EU has free movement with non-EU states (Norway, Iceland etc. ). Deals can be struck.
I'd become a strong rejoiner if the EU started to demonstrably solve its problems while the UK goes further south. Otherwise, I'd be happy with some form of free movement. This doesn't require a federal or confederal state.