Most new coins are moving away from PoW, so probably the party won't last long. When Ethereum goes PoS everyone will switch to smaller coins, making none of them profitable. There's won't be big new coins to replace Ethereum.
but i think when they switch to smaller coins ,the price of smaller coins will rise.
Its possible but it would take years or maybe early. I saw 2013 and how it ended. People says there is other coins to mine dont realize users is what keep mining alive. As a common user why use smaller coin when eth or btc is availible widely. Problem with smaller coins is up to how strong the marketing without that no money for the future.