I don't quite understand what a "known team" is. There are so many projects getting launched around the world every day. Living in, say, Austria, I wouldn't have a clue of the teams in Singapore, Germany, Switzerland or Ukraine. Each team is known to a specific community and geographically dependent. So yes, my view is that a project can be successful without a known team. Apart from that, there are so many factors that have a direct impact on the success, such as a properly written whitepaper with the product described in detail, consistent development of the product (road map), business model and tokenomics, legal side of all that (jurisdiction and regulations). I think the best way to decide on a future of a project is to do a thorough analysis and research.