The internet is great for connecting machines. HTTP(s) could even be used to transfer messages. Blockchain is good for maintaining a historical record. The farther down the chain you go, the harder it becomes to rewrite history. You pay for this feature by requiring everyone to permanently keep the whole shared historical record. Some workarounds for the permanent storage of the whole history exist but that’s blockchain in a basic form. The permanent record is a nice feature for things like financial transactions.
Blockchain bros tried to convince us blockchain is great for sharing information in an effort to increase its relevance. You may connect it for that reason. In their defence, blockchain can be used for data transfer, it’s just not that great at it.
Blockchain could be used to assert trust, but most problems have equally good or better alternative solutions for that. Very often these use digital signatures and public-private keypairs.
You may want to look at YaCy for a decentralised search engine.
Yes! You can create posts on Lemmy with the summary and a link to your site. The web is made of many platforms with links between then. Why not put your long-lived content on a platform you own? The web is a safe bet.