All I know is that when I took that word out it let me create the account. This was somewhere around the same time as your account creation. It might be more complicated than that, but I'm not about to try and reverse-engineer it.
The problem is the rules aren't specified, if you fall afoul of a rule you do not get told which rule it is, and the rules are AI-based decisions that are hard to even understand. If the process was transparent, it would be a lot easier to deal with.