There are node modules already that call into WASM-wrapped rust. (One of the most common source map generation packages does exactly that and it is very heavily installed by a lot of frameworks and packagers today.)

I don't think prettier is intending to do that in this case, they seem to want to continue to compete as a pure JS implementation but having a "worst case, we WASM wrap biome as the future of prettier" possibility opens up future opportunities and pushes "internal" competition.