Personal I think what he did wrong was changing the entire company system and rules .in fact he just changed everything so many restrictions and I guess that's why majority of advertising firms stopped advertising there. He just fucked up thinking everything could go his way. He should have followed the system a little and make changes more slowly. Even tho he is a genius ill say its not a very smart move from him 'Mr Twitter destroyer' 
Whatever you say here, Elon Musk will not hear it either, let alone believe you. Because the Twitter platform now belongs to Elon Musk, he is free to do whatever he wants and he could even destroy the Twitter platform as badly as he wants. Twitter platform users could provide better suggestions to Elon Musk, but Elon Musk also has the right to reject these suggestions and users also don't need to hope that their suggestions will be well received by Elon Musk.
You have to be able to separate someone's desires from someone's business goals because besides Elon Musk who already has the right to change the entire company system and regulations, you also have to know that Elon Musk is a businessman who will continue to do everything as long as his business can run smoothly and get good profits. very much although on the other hand it can invite more criticism from the users of the Twitter platform itself.