FrankenPHP is just Caddy + PHP, but in one binary.
The threads thing, the worker mode, etc., all of it is optional, but basic Caddy + PHP is already production-ready, I've been using this kind of setup for a while, and switching to FrankenPHP when you already have Caddy is completely harmless.
The only thing FrankenPHP does not is providing multiple versions of PHP in the same binary. For that, I'd still use Caddy + PHP-FPM, and it's fine.
