Ethereum Name System has been slept on for long enough. This is an alternative to traditional Domain Name Servers like Google DNS or GoDaddy where you can buy and register a website name like twitter.com. The difference between a .eth and a .com is the level of ownership and connectivity. Blockchain domains are connected to crypto wallets, NFTs, and your digital identity online. They are highly programable and I believe they will be a necessity for any person or company in the future when crypto is more mainstream.
In the twitter post above, you can see the owner of dcl.eth selling subdomains. The owner is of course Decentraland, one of the largest metaverses. You may want a dcl.eth domain if you were going to run a business on decentraland, for example university.decentraland.eth.