Question: Is it okay to launch multiple websites of the same content?
Answer: Yes, if it serves your objective(s). Some sites have specific reasons to setup multiple domains with identical content. But there is only one reason that will convince me of their necessity. In case two domains representing the same content appear on search results, they tend to push competing search results to the bottom of the first page or even further. For example, look at Xinhua Finance, a website that provides financial information. There are at least two websites that exist and each resembles the other.
I see only one reason for one to be set up if the other is already there. And that’s using SEO for either reputation management or brand promotion. Since that both domains are indexed, and that means when I search for “xfn” or “xinhua finance” or any relevant brand query, there is higher likelihood that Xinhua Finance will capture. While duplicate content is generally ignored by search engines, in this case maybe there is enough evidence for exemption for Xinhua Finance.
For other sites, it might require a little more creativity to achieve this goal. Otherwise, if only one website shows up, the other likely becomes a wasted effort.