PoS is not the solution to the problem of PoW coins, unfortunately mining is doomed, unless we have plenty of clean energy, in fact, there is plenty of clean energy, the issue is the cost of exploiting it. It's natural that BTC and other coins are under pressure on the cost of their mining and the trend of this pressure is to increase. The fact that the person or team that created the PoS coin has a quantity of that coin initially is not fair to those trying to obtain something using its resources. XCH is not entirely green, we are still far from a 100% green project.