At past POW was associated with security. People believed POS systems would not be as secure as POW. While they might not be but it's seen that they are secure enough for the people to use them without any issue. That's why there's an ever increasing number of POS coins and at current time, people don't care if the coin is POW or POS. A less energy intense POW is welcome as it would have benefits of both side but that feature alone won't make it a success. They'd need to go through the process of every coin to get the trust of people. In short, the algorithm is not a huge concern, the concern is its use and popularity.