“Folks have been building sqlite3 for the web since as far back as 2012 but this subproject is the first effort "officially" associated with the SQLite project, created with the goal of making WASM builds of the library first-class members of the family of supported SQLite deliverables.”
Browsers had a built-in SQL database once. WebSQL was SQLite, and it died because a standard needs more than one engine and every browser used the same one. Now the SQLite team ships its own official WebAssembly build, and the web gets SQLite back as a download. The standards process spent a decade arriving where it started.