Changing the ownership structure of Twitter won't change the character of the users - Thiel et al will continue to work on using their ownership of the userspace to sell their 'product'. As long as the users of the company remain Oligarchical Billionaires, that will remain the case. Changing the structure to give the users of the service full ownership will just accelerate that process.
Now, giving the audience of the service, the people with the @useraccounts, ownership of the service still won't achieve anything, at any level. Ownership by the audience will just be concentrated, in practical terms, in the hands of the users.
// @skematica @kdfrawg