Ethereum accounts are not tied to any service. They are just a public/private keypair so they can be used as portable usernames.
On the other hand, with the Ethereum protocol, you only have to rely on the public blockchain to attest/sign/prove ownership. You can choose the software and hardware that you use to secure your wallet too. You can even keep that wallet airgapped, totally offline and still authenticate using QR codes. If you were so inclined you could even run your own end point/node so you're not relying on any 3rd parties to attest/sign for you. It's a self sovereign online identity if you want it to be. It also has other benefits like the ability to store monetary value in the way of cryptocurrencies.
The ability to verify ownership of digital assets (tokens), like NFTs, and use those in creative ways like we have here. You can also use the Ethereum Name Service and tie a .ETH domain name to your public key, so people know that a message sent by frizlab.eth is really you, even if you have to get a new wallet address. It's your identity (frizlab.eth), your wallet, and with NFT's I think it could also verify and visualize your reputation or skillset online too, no matter what website you're on. Your identity owned by you and built on top of a world wide, immutable, distributed, consensus protocol. I wrote an article for Wordpress developers with my ideas, but I think it can apply to the web as a whole.
https://caches.xyz/the-rostrum/wordpress-web3-and-ethereum-w...
Again I haven't used this service and have no affiliation with them but do believe that we desperately need truly public digital infrastructure and I think Ethereum is a step in that direction.
Meanwhile, Mr. John "bro trust me bro your wallets secure bro nobody's going to just drop a viral token into your wallet to fuck with you bro" Ethereum is a 3rd party to the transaction between me and a website. I trust Ashley Madison with my password more than I trust the Web3 ecosystem and cryptobros to not fuck me over using the rules of their own rigged game.
"The third-party doctrine is a United States legal doctrine that holds that people who voluntarily give information to third parties—such as banks, phone companies, internet service providers (ISPs), and e-mail servers—have "no reasonable expectation of privacy" in that information. A lack of privacy protection allows the United States government to obtain information from third parties without a legal warrant and without otherwise complying with the Fourth Amendment prohibition against search and seizure without probable cause and a judicial search warrant."