The only way this can be avoided is by making sure that anyone who has closed an account on the same platform is automatically prevented from signing up to another casino sharing the platform, that way the player will know he isnt welcome to play there and it will save a lot of anger and frustration at a later stage.
I think it would be much better if the casinos are asking why the person wants to close their account.
To have this easy self exclusion where you just agree to something you don't read, because you maybe just want to get out of the casino, isn't so smart.
We all know that when there are laggings and errors constantly somewhere we just want to get away, never to see the place again. No good reason to get winnings confiscated.
Of course we should read the rules, but then there is that language question again. It's always in English.
I hadn't even heard the word self exclusion when I started to play. Many people are good in English but not that good. We do not understand the rules perfectly. We just trust the casinos.
Only emails and clear questions is what I would like to have.