Being issued on Stellar blockchain, PSH will automatically become tradable on the Stellar Decentralized Exchange (SDEX), hence, not necessarily required to be listed on any 3rd party crypto token exchanges (unlike e.g. ECR-20 tokens).
I think you entered the statement incorrectly here, You said unlike ERC-20 tokens? As I know, ERC-20 is an Ethereum tokens. Did you know that Ethereum is also have Decentralized Exchange? Even I thought their decentralized exchange is more than the stellar have. This will make a lot of people offended, because ERC-20 is the mostly used at this time.