[giantrobot]

The decentralized nature is immaterial if actual useful data/computations can't be performed by the network.

Ethereum's chain is about a terabyte and the total compute power is less than a single raspberry pi. So you can't store a meaningful amount of data on it without insane fees nor can you do much in the way of processing. This means anything interesting exists off-chain.

If interesting things exist off-chain...there's not much utility in having a blockchain at all. It's just a slow expensive ledger with no off-chain authority. Even if a transaction points to some content addressing P2P resource (IPFS etc), that content only exists while someone is hosting it from some machine(s) somewhere. When it stops being pinned (or conceptual equivalent) the record on the blockchain is worthless.

[publiush]

If it stops being seeded, then the content is worthless.

[giantrobot]

Seeding focuses on recent or popular content with a particular preference for popular recent content. Seeding is a LRU model so does not reliably serve long tail content. The age or popularity of content is not necessarily a measure of its value.