Main reasons are:
- Can build entire app (with SPA-type experience on the FE) in a single codebase
- No need to build any HTTP APIs
- Periodic tasks and managing in-memory state is super easy in Elixir. Eventually you might want to stick state somewhere which survives restarts (eg redis) but for the sake of moving quickly Elixir makes this really easy
- Newer versions of Phoenix/LiveView support html components so building out UIs now feels as nice as some of the tools in the FE ecosystem