The web once was mostly text, and it still had only handful then only one search engine... The web is huge you can't crawl it cheaply even if it was only text.

Yes someone can do the indexing and sign it and share it, but who cares, how is that different from visiting a website, the index remains centralized and thus the Indexer will both comply with censorship AND look for ways to make money to offset the cost... That is also ignoring personalisation and suggestions entirely... Just a dumb index.

Again, someone has to download the data to discover it ... And that can't be made cheap