The thing is, that won’t work well either. The UK had a very special position previously in the EU, like not adopting the Euro as currency and many other extra “perks” or whatever you want to call it. If they go back in they will likely not get any of those since otherwise it will look really bad for other countries that recently joined. Then people will be unhappy about joining again because it is not what they remembered. So, no, there is no winning with this one, damage is done.