Ethereum Classic is so cheap because it’s not in as great demand as Ethereum. Ethereum is a more popular cryptocurrency, so more people want to invest in it. Additionally, the Ethereum blockchain has a larger ecosystem of dapps and is widely used for decentralized finance. This increases demand for ether that can be used to power transactions on the Ethereum blockchain. The current version of Ethereum Classic just doesn’t have that same level of popularity, and therefore the demand and price aren’t as high.