If your public alternative can't win the users then "breaking the monopoly" will worsen the user experience. I don't want to live in that world - consider Telegram, a much better experience than WhatsApp, and it won over many users already. Evidently the monopoly is not as strong as is suggested. Telegram might not exist if there was a risk of losing the company. I don't want to be stuck with bad public software. In reality, when you destroy WhatsApp, people won't use the bad software, they will go to the next player and make it a "monopoly" because it most likely will be a better user experience.