It was sold under the premise that "Blockchain" projects can raise capital for their projects without having a working Blockchain -> hence ERC-20 tokens.

This allowed for accounting of who owns what meanwhile you develop what you promised.

Which was either a novel Blockchain that you would be swapped over to 1:1 or some bullshit they sold you meanwhile describing it as a "native ethereum asset".

Then came the idea of non fungible tokens...which were only really implemented how you know them after a few years.