I started to learn about crypto two months ago. Bitcoin, Monero, Ethereum etc. make total sense to me.

I can't, however, understand why it would make sense to decentralize large online platforms like Youtube and Facebook. Or let's say: I don't understand how this could work.

Bitcoin has a decentralized ledger where all transactions are stored. How would that ledger look for a decentralized Youtube or Facebook?

Or am I missing something? Does decentralization mean something different in this regard?

Thank you!

PS: I'm asking because I again and again read headlines that say something along the line of "everything will be decentralized".