In part because the cloud is just someone else's computer, and someone else's computer runs somewhere and is thus subject to human civilization and laws.

The cloud and p2p networks are different things.

Bittorrent (in its traditional use case of piracy) is still as illegal as ever and still going strong. So are cocaine sales, as is Uniswap's giant permissionless unregulated/unregistered securities market.

I think perhaps people overestimate the ability to effectively regulate.

Do any such services exist?

Bitcoin and Ethereum are the two largest.

Yea, they're barely available anywhere.