Many advantages! It's serverless... So you don't have to mess with configuring a webserver like nginx/caddy, or deal with a SQL database, or have to worry about resources like RAM, or worry someone will DDoS the relay.
Since it uses a Cloudflare worker and KV, it means the data is stored in all of Cloudflare PoPs around the world, which means the relay data will load from the nearest server for that person using the relay 😎