Is it possible to just return the errors to the client instead of returning a 500 by default?
I've done an overwrite of the error handler and this gives me the expected behavior:

fastify.register(require('fastify-sentry'), {
      dsn: '',
      errorHandler: (err, _, reply) => {
        if (err) {
          reply.send(err);
        }
      },
    });

This allows me to have decent validation errors without any additional efforts. Maybe best to implement a different default error handler?