> is tying web3 to several centralized front ends (Metamask/OpenSea).
You can't really lump both of those into the same bucket of "front-end". Metamask is a front-end, a user interface. OpenSea is more like middlewear that connects various front-end clients like Metamask to the backend database, and provides some additional functionality that's in any of the database's stored procedures or views. OpenSea also has its own front-end UI to its own service, but its core service is its API to the Ethereum database.
You can't really lump both of those into the same bucket of "front-end". Metamask is a front-end, a user interface. OpenSea is more like middlewear that connects various front-end clients like Metamask to the backend database, and provides some additional functionality that's in any of the database's stored procedures or views. OpenSea also has its own front-end UI to its own service, but its core service is its API to the Ethereum database.