Performance is likely part of it. The WASM solution looks faster than modernc: https://github.com/cvilsmeier/go-sqlite-bench
Faster was a by product. Maintainability was the goal.
API coverage, ergonomics, extensibility all rank higher in my book than performance.
An example I'd like to cite is sqlite-vec. Alex was able to build a Cgo-free version of it, on his own, which works fine with my bindings. This would be much harder to do with modernc.
https://github.com/asg017/sqlite-vec-go-bindings
I'm also adding support for building off the bedrock branch (begin concurrent, wal2). You just build the branch with wasi-sdk, then embed the resulting blob.