Ethereum does not have any brighter future than bitcoin. Bitcoin moves down, ethereum goes with it, that is how the market is been. ethereum is a fantastic smart contract platform but BTC will remain the leader.
But sending transaction in ethereum network is much cheaper than in blockchain. Maybe that was the key why reddit sticked with Ethereum. If this will be somehow connected with rewarding/upvoting, that cheap transactions is the solution, because people on reddit upvote much. If they upvote much, they will send more transaction, spend more - not the best tactics for platform users.