In order to attract liquidity, you need to create demand. For example, for POW to have liquidity, we need to make this platform grow. Imagine this platform has a million users and the POW token can be used for things like minting handles, boosting posts and articles, and gives you voting rights on features, then people will want to hold POW, not just because someone else might buy it, but because it has real value.

Roman coins outlived their civilization.

Yes but there was a civilization that used them for a long time. That is not yet the case for eCash or its tokens.